Our publications
Pressure-tuned many-body phases through Γ-K valleytronics in moiré bilayer WSe2
Marta Brzezińska, Sergii Grytsiuk, Malte Rösner, Marco Gibertini and Louk Rademaker
2D materials 12 1, 015003 (2025)
Recent experiments in twisted bilayer transition-metal dichalcogenides have revealed a variety of strongly correlated phenomena. To theoretically explore their origin, we combine here ab initio calculations with correlated model approaches to describe and study many-body effects in twisted bilayer…
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Doping Tunable CDW Phase Transition in Bulk 1T-ZrSe2
Andreas Ørsted, Alessandro Scarfato, Céline Barreteau, Enrico Giannini and Christoph Renner
Nano letters 25, acs.nanolett.4c06377, 1729-1735 (2025)
Tunable electronic properties in transition metal dichalcogenides (TMDs) are essential to further their use in device applications. Here, we present a comprehensive scanning tunneling microscopy and spectroscopy study of a doping-induced charge density wave (CDW) in semiconducting bulk…
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Non-Fermi liquid quasiparticles in strain-tuned Sr2RuO4
Andrew Scott Hunter, C. Putzke, F. B. Kugler, S. Beck, Edoardo Cappelli, Florian Margot, Michael Straub, Yann Alexanian, Jérémie Teyssier, A. de la Torre, K. W. Plumb, M. D. Watson, T. K. Kim, C. Cacho, N. C. Plumb, M. Shi, M. Radovic, J. Osiecki, C. Polley, D. A. Sokolov, A. P. Mackenzie, E. Berg, Antoine Georges, P. J. W. Moll, Anna Tamai and Felix Baumberger
Preprint (2025)
Interacting electrons can form metallic states beyond the Fermi liquid paradigm, a conceptual frontier of many-body physics mainly explored via bulk thermodynamics and transport. In contrast, the microscopics of anomalous single-particle excitations underlying non-Fermi liquid properties have…
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Investigating domain structures and superdomains in ferroelectric PbTiO3 based heterostructures on DyScO3
Ludovica Tovaglieri, Marios Hadjimichael, P. Torruella, Chih-Ying Hsu, Lukas Alexander Korosec, D. T. L. Alexander, Patrycja Paruch, Jean-Marc Triscone and Céline Lichtensteiger
APL materials 13 2, 021118 (2025)
This work focuses on the complex ferroelastic/ferroelectric domain structure in the prototypical ferroelectric PbTiO3 epitaxially strained on (110)o-oriented DyScO3 substrates, with a 22 nm-thick bottom SrRuO3 electrode. High quality epitaxial growth has been achieved from 7.2 nm (18 unit cells) up …
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Thoughts about boosting superconductivity
Dirk Van Der Marel
Physica. C, Superconductivity 632, 1354688 (2025)
In a superconductor electrons form pairs despite the Coulomb repulsion, as a result of an effective attractive interaction mediated by, for example, phonons. In the present paper DeGennes’ description of the dynamically screened Coulomb interaction is adopted for the effective interaction. This…
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X-Ray Absorption Spectroscopy to investigate precipitated oxides in Nb 3 Sn wires with an internal oxygen source
Gianmarco Bovone, Florin Buta, Francesco Lonardo, Marco Bonura, C. N. Borca, T. Huthwelker, S.c. Hopkins, A. Ballarino, T. Boutboul and Carmine Senatore
IEEE transactions on applied superconductivity 34 3, 6000205 (2024)
Internal oxidation can achieve significantly enhanced Jc in Nb 3 Sn wires, but the mechanism of oxygen transport and oxide precipitation is not fully understood. Our investigation employs X-ray Absorption Near-Edge Structure (XANES) spectroscopy, revealing insights into the…
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Assessing the Ubiquity of Bloch Domain Walls in Ferroelectric Lead Titanate Superlattices
Edoardo Zatterin, Petr Ondrejkovic, Louis Bastogne, Céline Lichtensteiger, Ludovica Tovaglieri, Daniel A. Chaney, Alireza Sasani, Tobias Schülli, Alexei Bosak, Steven Leake, Pavlo Zubko, Philippe Ghosez, Jirka Hlinka, Jean-Marc Triscone and Marios Hadjimichael
Physical review. X 14 4, 041052 (2024)
The observation of unexpected polarization textures such as vortices, skyrmions, and merons in various oxide heterostructures has challenged the widely accepted picture of ferroelectric domain walls as being Ising-like. Bloch components in the 180° domain walls of PbTiO 3 have recently been…
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Critical current degradation of commercial REBCO coated conductors under thermomechanical loads
Celia Lucas Esparseil, Pablo Cayado Llosa, Hannes Rijckaert, Konstantina Konstantopoulou, Davide Nardelli and Carmine Senatore
Superconductor science and technology 37 12, 125014 (2024)
The process to obtain a superconducting joint between Coated Conductors (CCs) involves the simultaneous application of temperature and transverse compressive pressure to promote the joining of the two adjacent RE BCO layers. We performed experiments to simulate this procedure by subjecting samples…
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Behavior of Water Adsorbates on Ferroelectric Thin Films
Loïc Musy
Thèse, 149 (2024)
Cette thèse explore, à l’aide de la microscopie à force atomique (AFM), le comportement des charges de surface sur les ferroélectriques, et la manière dont l’eau réagit selon l’orientation de la polarisation.
En complément des techniques AFM, des développements matériels (contrôleur…
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Ductile-to-brittle transition and yielding in soft amorphous materials: perspectives and open questions
Thibaut Divoux, Elisabeth Agoritsas, Stefano Aime, Catherine Barentin, Jean-Louis Barrat, Roberto Benzi, Ludovic Berthier, Dapeng Bi, Giulio Biroli, Daniel Bonn, Philippe Bourrianne, Mehdi Bouzid, Emanuela Del Gado, Hélène Delanoë-Ayari, Kasra Farain, Suzanne Fielding, Matthias Fuchs, Jasper van der Gucht, Silke Henkes, Maziyar Jalaal, Yogesh M Joshi, Anaël Lemaître, Robert L Leheny, Sébastien Manneville, Kirsten Martens, Wilson C K Poon, Marko Popović, Itamar Procaccia, Laurence Ramos, James A Richards, Simon Rogers, Saverio Rossi, Mauro Sbragaglia, Gilles Tarjus, Federico Toschi, Véronique Trappe, Jan Vermant, Matthieu Wyart, Francesco Zamponi and Davoud Zare
Soft matter 20 35, 6868-6888 (2024)
Soft amorphous materials are viscoelastic solids ubiquitously found around us, from clays and cementitious pastes to emulsions and physical gels encountered in food or biomedical engineering. Under an external deformation, these materials undergo a noteworthy transition from a solid to a liquid…
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Moiré magnetism in CrBr3 multilayers emerging from differential strain
Fengrui Yao, Dario Rossi, Ivo Antoniev Gabrovski, Volodymyr Multian, Nelson Hua, Kenji Watanabe, Takashi Taniguchi, Marco Gibertini, Ignacio Gutierrez Lezama, Louk Rademaker and Alberto Morpurgo
Nature communications 15 1, 10377 (2024)
Interfaces between twisted 2D materials host a wealth of physical phenomena originating from the long-scale periodicity associated with the resulting moiré structure. Besides twisting, an alternative route to create structures with comparably long-or even longer-periodicities is inducing a…
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Hall response of locally correlated two-dimensional electrons at low density
Giacomo Arturo Maria Morpurgo, Louk Rademaker, Christophe Berthod and Thierry Giamarchi
Physical review research 6 1, 013112 (2024)
We study the Hall constant in a homogeneous two-dimensional fluid of correlated electrons immersed in a perpendicular magnetic field, with special focus on the regime of low carrier density. The model consists of a one-band tight-binding model and a momentum-independent causal self-energy,…
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Experimental observation of repulsively bound magnons
Zhe Wang, Catalin-Mihai Halati, Jean-Sébastien Bernier, Alexey Ponomaryov, Denis I Gorbunov, Sandra Niesen, Oliver Breunig, J Michael Klopf, Sergei Zvyagin, Thomas Lorenz, Alois Loidl and Corinna Kollath
Nature 631 8022, 760-764 (2024)
Stable composite objects, such as hadrons, nuclei, atoms, molecules and superconducting pairs, formed by attractive forces are ubiquitous in nature. By contrast, composite objects stabilized by means of repulsive forces were long thought to be theoretical constructions owing to their fragility in…
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Effects of forward disorder on quasi-one-dimensional superconductors
Giacomo Arturo Maria Morpurgo and Thierry Giamarchi
Physical Review Research 6 2, 023291 (2024)
We study the competition between disorder and singlet superconductivity in a quasi-one-dimensional (1D) system. We investigate the applicability of the Anderson theorem, namely that time-reversal conserving (nonmagnetic) disorder does not impact the critical temperature, by opposition to…
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Anomalous cooling of bosons by dimensional reduction
Yanliang Guo, Hepeng Yao, Sudipta Dhar, Lorenzo Pizzino, Milena Horvath, Thierry Giamarchi, Manuele Landini and Hanns-Christoph Nägerl
Science Advances 10 7, eadk6870 (2024)
Cold atomic gases provide a remarkable testbed to study the physics of interacting many-body quantum systems. Temperatures are necessarily nonzero, but cooling to the ultralow temperatures needed for quantum simulation purposes or even simply measuring the temperatures directly on the system can…
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Observation of the 2D–1D crossover in strongly interacting ultracold bosons
Yanliang Guo, Hepeng Yao, Satwik Ramanjanappa, Sudipta Dhar, Milena Horvath, Lorenzo Pizzino, Thierry Giamarchi, Manuele Landini and Hanns-Christoph Nägerl
Nature Physics 20 6, 934-938 (2024)
Dimensionality plays an essential role in determining the nature and properties of a physical system. This is particularly evident in quantum systems, where interactions and fluctuations are enhanced in lower dimensions, leading to various different quantum effects. Here we show that strongly…
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Local Noise Spectroscopy of Wigner Crystals in Two-Dimensional Materials
Pavel E Dolgirev, Ilya Esterlis, Alexander A Zibrov, Mikhail D Lukin, Thierry Giamarchi and Eugene Demler
Physical Review Letters 132 24, 246504 (2024)
We propose local electromagnetic noise spectroscopy as a versatile and noninvasive tool to study Wigner crystal phases of strongly interacting two-dimensional electronic systems. In-plane imaging of the local noise is predicted to enable single-site resolution of the electron crystal when the…
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Transport and Nonreciprocity in Monitored Quantum Devices: An Exact Study
Joao Dos Santos Ferreira, Zizhuo Tony Jin, Jochen Mannhart, Thierry Giamarchi and Michele Filippone
Physical Review Letters 132 13, 136301 (2024)
We study noninteracting fermionic systems undergoing continuous monitoring and driven by biased reservoirs. Averaging over the measurement outcomes, we derive exact formulas for the particle and heat flows in the system. We show that these currents feature competing elastic and inelastic…
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Dirac impurity in a Luttinger liquid
Lorenzo Gotta and Thierry Giamarchi
Physical Review B 110 16, 165116 (2024)
We consider a linearly dispersing quantum impurity interacting through a contact density-density term with a one-dimensional (1D) superfluid described by the Tomonaga-Luttinger liquid theory. Using a linked-cluster expansion we characterize the impurity dynamics by calculating approximate…
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Conversion of angular momentum into charge at picosecond timescales in the LaAlO3 / SrTiO3 interface
Anas El Hamdi, Artem Levchuk, Cosimo Gorini, Margherita Boselli, Vincent Juvé, Tadele Orbula Otomalo, Gwenaëlle Vaudel, Stefano Gariglio, Pascal Ruello, Jean-Yves Chauleau and Michel Viret
Physical review. B 110 5, 054412 (2024)
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Switchable tribology of ferroelectrics
Seongwoo Cho, Iaroslav Gaponenko, Kumara Cordero-Edwards, Jordi Barceló-Mercader, Irene Arias, Daeho Kim, Céline Lichtensteiger, Jiwon Yeom, Loïc Musy, Hyunji Kim, Seung Min Han, Gustau Catalan, Patrycja Paruch and Seungbum Hong
Nature communications 15 387 (2024)
Switchable tribological properties of ferroelectrics offer an alternative route to visualize and control ferroelectric domains. Here, we observe the switchable friction and wear behavior of ferroelectrics using a nanoscale scanning probe—down domains have lower friction coefficients and show…
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High-Entropy Superconducting materials
Pablo Cayado Llosa and Jens Hänisch
High Entropy Alloys – Composition and Microstructure Design (2024)
High-entropy alloys are a rapidly evolving field of materials research and have gained increasing attention in recent years. Characterized by their multicomponent compositions, they were originally created by mixing a multitude of metallic elements and expanded the idea of traditional alloy design, …
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Evidence of Gd substitution for Y in YBCO films with Gd excess
P. Reale, V. Pinto, Pablo Cayado Llosa, G. Celentano, A. Angrisani Armenio, A. Rufoloni, A. Santoni and F. D’Acapito
Journal of alloys and compounds 983, 173921 (2024)
Gd-YBa2Cu3O7-δ (Gd-YBCO) thin films with 10 mol% and 20 mol% excess-Gd concentration with respect to Y were investigated at the Gd L3 and Y K core absorption edges by EXAFS spectroscopy with the aim of determining the local structure of the Gd…
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DSDApp: An Open-Access Tool for Definitive Screening Design
Ryoichiro Hayasaka, Jens Hänisch and Pablo Cayado Llosa
Journal of open research software 12 1, 2 (2024)
Definitive Screening Design (DSD) is a powerful design of experiment technique employed to find significant factors (parameters) and optimize the factor levels in many experiments of different fields. However, making its design and analyzing the obtained results usually requires expensive software…
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Anomalous electrons in a metallic kagome ferromagnet
Sandy Adhitia Ekahana, Y. Soh, Anna Tamai, Daniel Gosálbez-Martínez, Mengyu Yao, Andrew Scott Hunter, Wenhui Fan, Yihao Wang, Junbo Li, Armin Kleibert, C. A. F. Vaz, Junzhang Ma, Yimin Xiong, Oleg V. Yazyev, Felix Baumberger, Ming Shi and Gabriel Aeppli
Nature 627, 67-72 (2024)
Ordinary metals contain electron liquids within well-defined ‘Fermi’ surfaces at which the electrons behave as if they were non-interacting. In the absence of transitions to entirely new phases such as insulators or superconductors, interactions between electrons induce scattering that is…
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Phonon promoted charge density wave in topological kagome metal ScV6Sn6
Yong Hu, Junzhang Ma, Yinxiang Li, Yuxiao Jiang, Dariusz Jakub Gawryluk, Tianchen Hu, Jérémie Teyssier, Volodymyr Multian, Zhouyi Yin, Shuxiang Xu, Soohyeon Shin, Igor Plokhikh, Xinloong Han, Nicholas C. Plumb, Yang Liu, Jia-Xin Yin, Zurab Guguchia, Yue Zhao, Andreas P. Schnyder, Xianxin Wu, Ekaterina Pomjakushina, M. Zahid Hasan, Nanlin Wang and Ming Shi
Nature communications 15 1 (2024)
Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV 6 Sn 6 , a bilayer kagome metal featuring an intriguing $$\sqrt{3}\times\sqrt{3}\times3$$ 3 × 3 × 3…
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Delusive chirality and periodic strain pattern in moiré systems
Arpad Pasztor, Ishita Pushkarna and Christoph Renner
2D materials 11 3, 035017 (2024)
Geometric phase analysis (GPA) is a widely used technique for extracting displacement and strain fields from scanning probe images. Here, we demonstrate that GPA should be implemented with caution when several fundamental lattices contribute to the image, in particular in twisted heterostructures…
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Thickness effect on superconducting properties of niobium films for radio-frequency cavity applications
Antonio Bianchi, Marco Bonura, Carlota Pereira de Alemida Carlos, Stewart Leith, Guillaume Rosaz, Carmine Senatore and Walter Venturini Delsolaro
Superconductor science and technology 37 8, 085005 (2024)
Niobium-coated copper radio-frequency cavities are cost-effective alternatives to bulk niobium cavities, given the lower material costs of copper substrates and their operation in liquid helium at around 4.2 K. However, these cavities historically exhibited a gradual degradation in performance…
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Signatures of polarized chiral spin disproportionation in rare earth nickelates
Jiarui Li, Robert J. Green, Claribel Dominguez Ordonez, Abraham Levitan, Yi Tseng, Sara Catalano, Jennifer Fowlie, Ronny Sutarto, Fanny Rodolakis, Lucas Korol, Jessica L. McChesney, John W. Freeland, Dirk Van Der Marel, Marta Gibert and Riccardo Comin
Nature communications 15 1, 7427 (2024)
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Feedback loop dependent charge density wave imaging by scanning tunneling spectroscopy
Alessandro Scarfato, Arpad Pasztor, Lihuan Sun, Ivan Maggio-Aprile, Vincent Pasquier, Tejas Parasram Singar, Andreas Ørsted, Ishita Pushkarna, Marcello Spera, Enrico Giannini and Christoph Renner
Physical review. B 110 8, 085109 (2024)
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Magnets for a Muon Collider—Needs and Plans
L. Bottura, C. Accettura, N. Amemiya, B. Auchmann, J.s. Berg, A. Bersani, A. Bertarelli, F. Boattini, B. Bordini, P. Borges de Sousa, M. Breschi, B. Caiffi, X. Chaud, F. Debray, A. Dudarev, M. Eisterer, S. Fabbri, S. Farinon, P. Ferracin, H. De Gersem, A. Kario, A. Kolehmainen, J. Kosse, J. Lorenzo Gomez, R. Losito, S. Mariotto, M. Mentink, T. Mulder, R. Musenich, D. Novelli, T. Ogitsu, M. Palmer, J. Pavan, H. Piekarz, A. Portone, L. Quettier, E. Rochepault, L. Rossi, T. Salmi, H. Schneider-Muntau, Carmine Senatore, M. Statera, H.h.j. Ten Kate, P. Testoni, G. Vallone, A. Verweij, R. Van Weelderen, M. Wozniak, A. Yamamoto, Y. Yang, Y. Zhai and A. Zlobin
IEEE transactions on applied superconductivity 34 5 (2024)
We describe the magnet challenges for a Muon Collider, an exciting option considered for the future of particle physics at the energy frontier. Starting from the comprehensive work performed by the US Muon Accelerator Program, we have reviewed the performance specifications dictated by beam physics …
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Controlling crystal cleavage in Focused Ion Beam shaped specimens for surface spectroscopy
Andrew Scott Hunter, C. Putzke, Iaroslav Gaponenko, Anna Tamai, Felix Baumberger and P. J. W. Moll
Review of scientific instruments 95, 033905 (2024)
Our understanding of quantum materials is commonly based on precise determinations of their electronic spectrum by spectroscopic means, most notably angle-resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy (STM). Both require atomically clean and flat crystal surfaces…
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Conceptual design of an HTS Canted Cosine Theta dipole magnet for research and hadron therapy accelerators
E. De Matteis, A. Ballarino, D. Barna, A. Carloni, A. Echeandia, G. Kirby, T. Lecrevisse, J. Lucas, S. Mariotto, J. van Nugteren, M. Prioli, L. Rossi, Carmine Senatore, M. Sorbi, S. Sorti, M. Statera, F. Toral and R.u. Valente
IEEE transactions on applied superconductivity 34 5, 4402505 (2024)
The European project IFAST’s WP8 Innovative Superconducting Magnets aims to develop the technology of Canted Cosine Theta (CCT) magnets wound with High-Temperature Superconductors (HTS). Superconducting magnets could lower the size and cost of synchrotrons and gantries for research and hadron…
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Observation of naturally canalized phonon polaritons in LiV2O5 thin layers
Ana I. F. Tresguerres-Mata, Christian Lanza, Javier Taboada Gutierrez, Joseph. R. Matson, Gonzalo Álvarez-Pérez, Masahiko Isobe, Aitana Tarazaga Martín-Luengo, Jiahua Duan, Stefan Partel, María Vélez, Javier Martín-Sánchez, Alexey Y. Nikitin, Joshua D. Caldwell and Pablo Alonso-González
Nature communications 15 1, 2696 (2024)
Polariton canalization is characterized by intrinsic collimation of energy flow along a single crystalline axis. This optical phenomenon has been experimentally demonstrated at the nanoscale by stacking and twisting van der Waals (vdW) layers of α-MoO3, by combining α-MoO3…
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Loss of memory of an elastic line on its way to limit cycles
Elisabeth Agoritsas and Jonathan Barés
Physical review. E 109 4, L042901 (2024)
Oscillatory-driven amorphous materials forget their initial configuration and converge to limit cycles. Here we investigate this memory loss under a nonquasistatic drive in a minimal model system, with quenched disorder and memory encoded in a spatial pattern, where oscillating protocols are…
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Type-II superconductivity in the Dirac semimetal PdTe2
Ritu Gupta, Catherine Witteveen, Debarchan Das, Fabian von Rohr and Rustem Khasanov
Physical review. B 109 13, 134507 (2024)
We report on the microscopic superconducting properties of the Dirac semimetal PdTe2. In this study, we have focused on mosaic crystals of PdTe2, and used detailed zero-field and transverse-field muon-spin relaxation/rotation (μSR), ac-magnetic susceptibility, and resistivity measurements to…
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Anomalous temperature dependence of phonon lifetimes in metallic VO2
Willem Rischau, Artem Korshunov, Volodymyr Multian, Sara Almudena Lopez Paz, Chubin Huang, Lucia Varbaro, Jérémie Teyssier, Yoav Kalcheim, Stefano Gariglio, Alexei Bosak, Jean-Marc Triscone and Javier del Valle
Physical review. B, Condensed matter 109, 094122 (2024)
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Highly confined epsilon-near-zero and surface phonon polaritons in SrTiO3 membranes
Ruijuan Xu, Iris Crassee, Hans A. Bechtel, Yixi Zhou, Adrien Bercher, Lukas Alexander Korosec, Willem Rischau, Jérémie Teyssier, Kevin J. Crust, Yonghun Lee, Stephanie N. Gilbert Corder, Jiarui Li, Jennifer A. Dionne, Harold Y. Hwang, Alexey Kuzmenko and Yin Liu
Nature communications 15 1, 4743 (2024)
Recent theoretical studies have suggested that transition metal perovskite oxide membranes can enable surface phonon polaritons in the infrared range with low loss and much stronger subwavelength confinement than bulk crystals. Such modes, however, have not been experimentally observed so far….
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Resistive switching of VO2 films grown on a thermal insulator
Willem Rischau, Stefano Gariglio, Jean-Marc Triscone and Javier del Valle
Physical review applied 22 1, 014021 (2024)
Many correlated oxides feature an insulator-to-metal transition as the temperature is increased. In thin films, this transition can be electrically induced by localized Joule heating, resulting in volatile resistive switching. Considering the importance of thermal effects, the thermal conductivity…
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Structural study of nickelate based heterostructures
Lucia Varbaro, Bernat Mundet Bolos, Subhadeep Bandyopadhyay, Claribel Dominguez Ordonez, Jennifer Fowlie, Lukas Alexander Korosec, Chih-Ying Hsu, Duncan T. L. Alexander, Philippe Ghosez and Jean-Marc Triscone
APL materials 12 3, 031104 (2024)
Heterostructures consisting of SmNiO3 and NdNiO3 alternating layers with additional LaAlO3 spacer layers were grown and fully characterized by means of x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy. A change in the orientation of the orthorhombic…
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The Changing Landscape of Materials Discovery
Fabian von Rohr
Chimia 78 12, 855-861 (2024)
In this perspective, we will discuss the impact of some of the most recent advancements in materials discovery, particularly focusing on the role of robotics, artificial intelligence, and self-driving laboratories, as well as their implications for the Swiss research landscape. While it seems…
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Influence of magnetism on vertical hopping transport in CrSBr
Xiaohanwen Lin, Fan Wu, Sara Almudena Lopez Paz, Fabian von Rohr, Marco Gibertini, Ignacio Gutierrez Lezama and Alberto Morpurgo
Physical review research 6 1, 013185 (2024)
We investigate the c -direction conduction in CrSBr in the linear regime, which is not accessible in other van der Waals (vdW) magnetic semiconductors, because of the unmeasurably low current. The resistivity, which is 10 8 − 10 11 times larger than in the a and b directions, exhibits magnetic…
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Ti4Ir2O : A time reversal invariant fully gapped unconventional superconductor
Debarchan Das, KeYuan Ma, Jan Jaroszynski, Vahid Sazgari, Tomasz Klimczuk, Fabian von Rohr and Zurab Guguchia
Physical review. B 110 17, 174507 (2024)
Here we report muon spin rotation ( μ SR ) experiments on the temperature and field dependence of the effective magnetic penetration depth λ ( T ) in the η -carbide-type suboxide Ti 4 Ir 2 O , a superconductor with a considerably high upper critical field. The temperature dependence of λ ( T ) …
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Bonding states underpinning structural transitions in IrTe2 observed with micro-ARPES
C. W. Nicholson, M. D. Watson, A. Pulkkinen, M. Rumo, G. Kremer, K. Y. Ma, Fabian von Rohr, C. Cacho and C. Monney
Physical review. B 110 20, 205123 (2024)
Competing interactions in low-dimensional materials can produce nearly degenerate electronic and structural phases. We investigate structural phase transitions in layered IrTe 2 for which a number of potential transition mechanisms have been postulated. The spatial coexistence of multiple phases…
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Quantum oscillation signatures of the Bloch-Grüneisen temperature in the Dirac semimetal ZrTe5
S. Galeski, K. Araki, O. K. Forslund, R. Wawrzyńczak, H. F. Legg, P. K. Sivakumar, U. Miniotaite, F. Elson, M. Månsson, Catherine Witteveen, Fabian von Rohr, A. Q. R. Baron, D. Ishikawa, Q. Li, G. Gu, L. X. Zhao, W. L. Zhu, G. F. Chen, Y. Wang, S. S. P. Parkin, D. Grobunov, S. Zherlitsyn, B. Vlaar, D. H. Nguyen, S. Paschen, P. Narang, C. Felser, J. Wosnitza, T. Meng, Y. Sassa, S. A. Hartnoll and J. Gooth
Physical review. B 110 12, L121103 (2024)
The electron-phonon interaction is in many ways a solid state equivalent of quantum electrodynamics. Being always present, the e-p coupling is responsible for the intrinsic resistance of metals at finite temperatures, making it one of the most fundamental interactions present in solids. In typical…
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Nonmonotonic superconducting transition temperature and large bulk modulus in the alloy superconductor Nb4Rh2C1−δ
Lifen Shi, Keyuan Ma, Binbin Ruan, Ningning Wang, Jun Hou, Pengfei Shan, Pengtao Yang, Jianping Sun, Genfu Chen, Zhian Ren, Fabian von Rohr, Bosen Wang and Jinguang Cheng
Physical review. B 110 21, 214520 (2024)
We revised normal-state and superconducting properties of an alloy superconductor Nb4Rh2C1−𝛿 through electrical transport, magnetic susceptibility, and specific heat. Our results reveal that it is a Pauli paramagnetic bad metal, a strongly coupled superconductor with specific heat…
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Direct imaging of the magnetoelectric coupling in multiferroic BaTiO3/La0.9Ba0.1MnO3
F. Stramaglia, G. Panchal, Ludovica Tovaglieri, Céline Lichtensteiger, F. Nolting and C. A. F. Vaz
Journal of vacuum science & technology. A. Vacuum, surfaces, and films 42 2, 023208 (2024)
We report the direct imaging of the magnetic response of a 4.8 nm La0.9Ba0.1MnO3 film to the voltage applied across a 5 nm BaTiO3 film in a BaTiO3/La0.9Ba0.1MnO3 multiferroic heterostructure using x-ray photoemission electron microscopy (XPEEM). Specifically, we have written square…
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Dual Second Harmonic Generation and Up-Conversion Photoluminescence Emission in Highly-Optimized LiNbO3 Nanocrystals Doped and Co-Doped with Er3+ and Yb3+
Kévin Bredillet, Florian Riporto, Tianhao Guo, Ameni Dhouib, Volodymyr Multian, Virginie Monnier, Paulí Figueras Llussà, Sandrine Beauquis, Luigi Bonacina, Yannick Mugnier and Ronan Le Dantec
Nanoscale (2024)
Preparation from the aqueous alkoxide route of doped and co-doped lithium niobate nanocrystals with Er 3+ and Yb 3+ ions, and detailed investigations of their optical properties are presented in this comprehensive…
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Nature of metallic and insulating domains in the CDW system 1T-TaSe2
Michael Straub, Francesco Petocchi, Catherine Witteveen, F. B. Kugler, Andrew Scott Hunter, Yann Alexanian, Gianmarco Gatti, Salony Mandloi, C. Polley, G. Carbone, J. Osiecki, Fabian von Rohr, Antoine Georges, Felix Baumberger and Anna Tamai
Preprint (2024)
We study the electronic structure of bulk 1T-TaSe$_2$ in the charge density wave phase at low temperature. Our spatially and angle resolved photoemission (ARPES) data show insulating areas coexisting with metallic regions characterized by a chiral Fermi surface and moderately correlated…
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Fermi surface and pseudogap in highly doped Sr2IrO4
Yann Alexanian, A. de la Torre, Siobhan Mckeown Walker, Michael Straub, Gianmarco Gatti, Andrew Scott Hunter, Salony Mandloi, Edoardo Cappelli, Sara Ricco, Flavio Yair Bruno, M. Radovic, N. C. Plumb, M. Shi, J. Osiecki, C. Polley, T. K. Kim, P. Dudin, M. Hoesch, R. S. Perry, Anna Tamai and Felix Baumberger
Preprint (2024)
The fate of the Fermi surface in bulk electron-doped Sr$_{2}$IrO$_{4}$ remains elusive, as does the origin and extension of its pseudogap phase. Here, we use high-resolution angle-resolved photoelectron spectroscopy (ARPES) to investigate the electronic structure of Sr$_{2-x}$La$_{x}$IrO$_{4}$ up…
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Landau-phonon polaritons in Dirac heterostructures
Lukas Wehmeier, Suheng Xu, Rafael A Mayer, Brian Vermilyea, Makoto Tsuneto, Michael Dapolito, Rui Pu, Zengyi Du, Xinzhong Chen, Wenjun Zheng, Ran Jing, Zijian Zhou, Kenji Watanabe, Takashi Taniguchi, Adrian Gozar, Qiang Li, Alexey Kuzmenko, G Lawrence Carr, Xu Du, Michael M Fogler, D N Basov and Mengkun Liu
Science advances 10 37, eadp3487 (2024)
Polaritons are light-matter quasiparticles that govern the optical response of quantum materials at the nanoscale, enabling on-chip communication and local sensing. Here, we report Landau-phonon polaritons (LPPs) in magnetized charge-neutral graphene encapsulated in hexagonal boron nitride (hBN)….
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Unveiling the Mechanism of Phonon-Polariton Damping in α-MoO3
Javier Taboada Gutierrez, Yixi Zhou, Ana I F Tresguerres-Mata, Christian Lanza, Abel Martínez-Suárez, Gonzalo Álvarez-Pérez, Jiahua Duan, José Ignacio Martín, María Vélez, Iván Prieto, Adrien Bercher, Jérémie Teyssier, Ion Errea, Alexey Y Nikitin, Javier Martín-Sánchez, Alexey Kuzmenko and Pablo Alonso-González
ACS photonics 11 9, 3570-3577 (2024)
Phonon polaritons (PhPs), light coupled to lattice vibrations, in the highly anisotropic polar layered material molybdenum trioxide (α-MoO3 ) are currently the focus of intense research efforts due to their extreme subwavelength field confinement, directional propagation, and…
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Infrared Spectroscopy for Diagnosing Superlattice Minibands in Twisted Bilayer Graphene near the Magic Angle
Geng Li, Roshan Krishna Kumar, Petr Stepanov, Pierre A Pantaleón, Zhen Zhan, Hitesh Agarwal, Adrien Bercher, Julien Barrier, Kenji Watanabe, Takashi Taniguchi, Alexey Kuzmenko, Francisco Guinea, Iacopo Torre and Frank H L Koppens
Nano letters 24 50, 15956-15963 (2024)
Twisted bilayer graphene (TBG) represents a highly tunable, strongly correlated electron system. However, understanding the single-particle band structure alone has been challenging due to a lack of spectroscopic measurements over a broad energy range. Here, we probe the band structure of TBG…
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Chemical Principles of Intrinsic Topological Superconductors
Fabian von Rohr
Chemistry of materials 35 22, 9455-9472 (2023)
The concept of topological superconductivity has attracted immense interest in the physics community recently for several reasons: First, topological superconductors represent new phases of matter, which are topologically distinct from any other known phase of matter. Second, their discovery would…
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Vortex-core spectroscopy of d-wave cuprate high-temperature superconductors
Ivan Maggio-Aprile, Tejas Parasram Singar, Christophe Berthod, Tim Gazdic, Jens Erik Bruer and Christoph Renner
Physica. C, Superconductivity 615, 1354386 (2023)
The mechanism of high-temperature superconductivity remains one of the great challenges of contemporary physics. Here, we review efforts to image the vortex lattice in copper oxide-based high-temperature superconductors and to measure the characteristic electronic structure of the vortex core of a…
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Terahertz Twistoptics–Engineering Canalized Phonon Polaritons
Maximilian Obst, Tobias Nörenberg, Gonzalo Álvarez-Pérez, Thales V. A. G. de Oliveira, Javier Taboada Gutierrez, Flávio H. Feres, Felix G. Kaps, Osama Hatem, Andrei Luferau, Alexey Y. Nikitin, J. Michael Klopf, Pablo Alonso-González, Susanne C. Kehr and Lukas M. Eng
ACS nano 17 19, 19313-19322 (2023)
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Universal Scaling near Band-Tuned Metal-Insulator Phase Transitions
Simone Fratini, Sergio Ciuchi, Vladimir Dobrosavljević and Louk Rademaker
Physical review letters 131 19, 196303 (2023)
We present a theory for band-tuned metal-insulator transitions based on the Kubo formalism. Such a transition exhibits scaling of the resistivity curves, in the regime where Tτ>1 or μτ>1, where τ is the scattering time and μ the chemical potential. At the critical value of the chemical…
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EuCd2As2 : A Magnetic Semiconductor
D. Santos-Cottin, I. Mohelský, J. Wyzula, F. Le Mardelé, Itzik Kapon, S. Nasrallah, N. Barišić, I. Živković, J. r. Soh, F. Guo, K. Rigaux, M. Puppin, J. h. Dil, B. Gudac, Z. Rukelj, M. Novak, Alexey Kuzmenko, C. c. Homes, Tomasz Dietl, M. Orlita and Ana Akrap
Physical review letters 131 18, 186704 (2023)
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Nanoscale domain engineering in SrRuO3 thin films
Céline Lichtensteiger, Chia-Ping Su, Iaroslav Gaponenko, Marios Hadjimichael, Ludovica Tovaglieri, Patrycja Paruch, Alexandre Gloter and Jean-Marc Triscone
APL materials 11 10, 101110 (2023)
We investigate nanoscale domain engineering via epitaxial coupling in a set of SrRuO3/PbTiO3/SrRuO3 heterostructures epitaxially grown on (110)o-oriented DyScO3 substrates. The SrRuO3 layer thickness is kept at 55 unit cells, whereas the PbTiO3 layer is grown to thicknesses of 23, 45, and 90 unit…
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Thermal and electrostatic tuning of surface phonon-polaritons in LaAlO3/SrTiO3 heterostructures
Yixi Zhou, Adrien Waelchli, Margherita Boselli, Iris Crassee, Adrien Bercher, Weiwei Luo, Jiahua Duan, J.l.m. van Mechelen, Dirk Van Der Marel, Jérémie Teyssier, Willem Rischau, Lukas Alexander Korosec, Stefano Gariglio, Jean-Marc Triscone and Alexey Kuzmenko
Nature communications 14 1, 7686 (2023)
Phonon polaritons are promising for infrared applications due to a strong light-matter coupling and subwavelength energy confinement they offer. Yet, the spectral narrowness of the phonon bands and difficulty to tune the phonon polariton properties hinder further progress in this field. SrTiO…
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Semiclassical theory of quantum stochastic resistors
Zizhuo Tony Jin, Joao Dos Santos Ferreira, Michel Bauer, Michele Filippone and Thierry Giamarchi
Physical Review Research 5 1, 013033 (2023)
We devise a semiclassical model to describe the transport properties of low-dimensional fermionic lattices under the influence of external quantum stochastic noise. These systems behave as quantum stochastic resistors, where the bulk particle transport is diffusive and obeys the Ohm/Fick’s law….
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Localization induced by spatially uncorrelated subohmic baths in one dimension
Saptarshi Majumdar, Laura Foini, Thierry Giamarchi and Alberto Rosso
Physical Review B 108 20, 205138 (2023)
We study an incommensurate XXZ spin chain coupled to a collection of local harmonic baths. At zero temperature, by varying the strength of the coupling to the bath the chain undergoes a quantum phase transition between a Luttinger liquid phase and a spin-density wave (SDW). Our results are…
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Bath-induced phase transition in a Luttinger liquid
Saptarshi Majumdar, Laura Foini, Thierry Giamarchi and Alberto Rosso
Physical Review B 107 16, 165113 (2023)
We study an XXZ spin chain, where each spin is coupled to an independent ohmic bath of harmonic oscillators at zero temperature. Using bosonization and numerical techniques, we show the existence of two phases separated by a Kosterlitz-Thouless transition. At low coupling with the bath, the chain…
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Strongly-interacting bosons at 2D-1D dimensional crossover
Hepeng Yao, Lorenzo Pizzino and Thierry Giamarchi
SciPost Physics 15 2, 050 (2023)
We study a two dimensional (2D) system of interacting quantum bosons, subjected to a continuous periodic potential in one direction. The correlation of such system exhibits a dimensional crossover between a canonical 2D behavior with Berezinski-Kosterlitz-Thouless (BKT) properties and a…
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Observation of universal Hall response in strongly interacting Fermions
T.-W. Zhou, G. Cappellini, D. Tusi, L. Franchi, J. Parravicini, C. Repellin, Sebastian Greschner, M. Inguscio, Thierry Giamarchi, M. Filippone, J. Catani and L. Fallani
Science 381 6656, 427-430 (2023)
The Hall effect, which originates from the motion of charged particles in magnetic fields, has deep consequences for the description of materials, extending far beyond condensed matter. Understanding such an effect in interacting systems represents a fundamental challenge, even for small magnetic…
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Competition between Carrier Injection and Structural Distortions in Electron‐Doped Perovskite Nickelate Thin Films
Marios Hadjimichael, Bernat Mundet Bolos, Claribel Dominguez Ordonez, Adrien Waelchli, Gabriele De Luca, Jonathan Spring, Simon Jöhr, Siobhan Mckeown Walker, Cinthia Piamonteze, Duncan T. L. Alexander, Jean-Marc Triscone and Marta Gibert
Advanced Electronic Materials, 2201182 (2023)
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Dynamics of dispersive collective modes in correlated matter
Francesco Barantani
Thèse (2023)
Complex systems exhibit emergent properties characterized by fascinating phenomena. These are a direct consequence of the interplay among different constituents and cannot simply be reduced to independent contributions.
In the study of materials, the number of particles that have to be considered…
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Observation of flat Γ moiré bands in twisted bilayer WSe2
Gianmarco Gatti, Julia Issing, Louk Rademaker, Florian Margot, Tobias A. de Jong, Sense Jan van der Molen, Jérémie Teyssier, Timur K. Kim, Matthew D. Watson, Cephise Cacho, Pavel Dudin, José Avila, Kumara Cordero Edwards, Patrycja Paruch, Nicolas Ubrig, Ignacio Gutierrez Lezama, Alberto Morpurgo, Anna Tamai and Felix Baumberger
Physical review letters 131 4, 046401 (2023)
The recent observation of correlated phases in transition metal dichalcogenide moir\’e systems at integer and fractional filling promises new insight into metal-insulator transitions and the unusual states of matter that can emerge near such transitions. Here, we combine real- and momentum-space…
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Designing spin and orbital sources of Berry curvature at oxide interfaces
Edouard Lesne, Yildiz G. Saǧlam, Raffaele Battilomo, Maria Teresa Mercaldo, Thierry C. van Thiel, Ulderico Filippozzi, Canio Noce, Mario Cuoco, Gary A. Steele, Carmine Ortix and Andrea Caviglia
Nature materials (2023)
Quantum materials can display physical phenomena rooted in the geometry of electronic wavefunctions. The corresponding geometric tensor is characterized by an emergent field known as the Berry curvature (BC). Large BCs typically arise when electronic states with different spin, orbital or…
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Advanced Catalyst for CO2 Photo‐Reduction: From Controllable Product Selectivity by Architecture Engineering to Improving Charge Transfer Using Stabilized Au Clusters
Abolfazl Ziarati, Jiangtao Zhao, Jafar Afshani Aghajari, Rania Kazan, Ariel Francis Perez Mellor, Arnulf Rosspeintner, Siobhan Mckeown Walker and Thomas Buergi
Small 19 24, 2207857 (2023)
Despite enormous progress and improvement in photocatalytic CO 2 reduction reaction (CO 2 RR), the development of photocatalysts that suppress H 2 evolution reaction (HER), during CO 2 RR, remains still a challenge. Here, new insight is presented for…
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Anomalous Impact of Mechanochemical Treatment on the Na‐ion Conductivity of Sodium Closo‐Carbadodecaborate Probed by X‐Ray Raman Scattering Spectroscopy
Valerio Gulino, Alessandro Longo, Laura M. de Kort, Hendrik P. Rodenburg, Fabrizio Murgia, Matteo Brighi, Radovan Cerny, Christoph J. Sahle, Martin Sundermann, Hlynur Gretarsson, Frank de Groot and Peter Ngene
Small methods 8 1, 2300833 (2023)
Solid‐state sodium ion conductors are crucial for the next generation of all‐solid‐state sodium batteries with high capacity, low cost, and improved safety. Sodium closo‐carbadodecaborate (NaCB 11 H 12 ) is an attractive Na‐ion conductor owing to its high thermal,…
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Impact of deoxygenation/reoxygenation processes on the superconducting properties of commercial coated conductors
Pablo Cayado Llosa, Marco Bonura, Celia Lucas Esparseil, Enora Saule, Hannes Rijckaert, Tommaso Bagni, Konstantina Konstantopoulou, Matteo Alessandrini and Carmine Senatore
Scientific reports 13 1, 16917 (2023)
We report the evolution of the superconducting properties of a commercial coated conductor during deoxygenation and reoxygenation processes. By analyzing the changes on the critical temperature, T c , and critical current density, J c , at 4 and 77 K, we have identified the…
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Competition between magnetic interactions and structural instabilities leading to itinerant frustration in the triangular lattice antiferromagnet LiCrSe2
Elisabetta Nocerino, Shintaro Kobayashi, Catherine Witteveen, Ola K. Forslund, Nami Matsubara, Chiu Tang, Takeshi Matsukawa, Akinori Hoshikawa, Akihiro Koda, Kazuyoshi Yoshimura, Izumi Umegaki, Yasmine Sassa, Fabian von Rohr, Vladimir Pomjakushin, Jess H. Brewer, Jun Sugiyama and Martin Månsson
Communications materials 4 1, 81 (2023)
LiCrSe 2 constitutes a recent valuable addition to the ensemble of two-dimensional triangular lattice antiferromagnets. In this work, we present a comprehensive study of the low temperature nuclear and magnetic structure established in this material. Being subject to a strong…
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Characteristic length scales of the electrically induced insulator-to-metal transition
Teodor Luibrand, Adrien Bercher, Rodolfo Rocco, Farnaz Tahouni-Bonab, Lucia Varbaro, Willem Rischau, Claribel Dominguez Ordonez, Yixi Zhou, Weiwei Luo, Soumen Bag, Lorenzo Fratino, Reinhold Kleiner, Stefano Gariglio, Dieter Koelle, Jean-Marc Triscone, Marcelo J. Rozenberg, Alexey B. Kuzmenko, Stefan Guénon and Javier Del Valle Granda
Physical review research 5, 013108 (2023)
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Roadmap on artificial intelligence and big data techniques for superconductivity
Mohammad Yazdani-Asrami, Wenjuan Song, Antonio Morandi, Giovanni De Carne, Joao Murta-Pina, Anabela Pronto, Roberto Oliveira, Francesco Grilli, Enric Pardo, Michael Parizh, Boyang Shen, Tim Coombs, Tiina Salmi, Di Wu, Eric Coatanea, Dominic A Moseley, Rodney A Badcock, Mengjie Zhang, Vittorio Marinozzi, Nhan Tran, Maciej Wielgosz, Andrzej Skoczeń, Dimitrios Tzelepis, Sakis Meliopoulos, Nuno Vilhena, Guilherme Sotelo, Zhenan Jiang, Veit Große, Tommaso Bagni, Diego Mauro, Carmine Senatore, Alexey Mankevich, Vadim Amelichev, Sergey Samoilenkov, Tiem Leong Yoon, Yao Wang, Renato P Camata, Cheng-Chien Chen, Ana Maria Madureira and Ajith Abraham
Superconductor science and technology 36 4, 043501 (2023)
This paper presents a roadmap to the application of AI techniques and big data (BD) for different modelling, design, monitoring, manufacturing and operation purposes of different superconducting applications. To help superconductivity researchers, engineers, and manufacturers understand the…
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Controlling Magnetism with Light in a Zero Orbital Angular Momentum Antiferromagnet
Mattias Matthiesen, Jorrit R. Hortensius, Samuel Mañas-Valero, Itzik Kapon, Dumitru Dumcenco, Enrico Giannini, Makars Šiškins, Boris A. Ivanov, Herre S. J. van der Zant, Eugenio Coronado, Alexey Kuzmenko, Dmytro Afanasiev and Andrea Caviglia
Physical review letters 130 7, 076702 (2023)
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Mapping the complex evolution of ferroelastic/ferroelectric domain patterns in epitaxially strained PbTiO3 heterostructures
Céline Lichtensteiger, Marios Hadjimichael, Edoardo Zatterin, Chia-Ping Su, Iaroslav Gaponenko, Ludovica Tovaglieri, Patrycja Paruch, Alexandre Gloter and Jean-Marc Triscone
APL materials 11 6, 061126 (2023)
We study the complex ferroelastic/ferroelectric domain structure in the prototypical ferroelectric PbTiO3 epitaxially strained on (110)o-oriented DyScO3 substrates, using a combination of atomic force microscopy, laboratory and synchrotron x-ray diffraction, and high resolution scanning…
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Towards a muon collider
European physical journal. C, Particles and fields 83 9, 864 (2023)
A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon…
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Transfer learning application of self-supervised learning in ARPES
Sandy Adhitia Ekahana, Genta Indra Winata, Y. Soh, Anna Tamai, Milan Radovic, Gabriel Aeppli and Ming Shi
Machine learning: science and technology (2023)
There is a growing recognition that electronic band structure is a local property of materials and devices, and there is steep growth in capabilities to collect the relevant data. New photon sources, from small-laboratory-based lasers to free electron lasers, together with focussing beam optics and …
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Infrared nano-imaging of Dirac magnetoexcitons in graphene
Michael Dapolito, Makoto Tsuneto, Wenjun Zheng, Lukas Wehmeier, Suheng Xu, Xinzhong Chen, Jiacheng Sun, Zengyi Du, Yinming Shao, Ran Jing, Shuai Zhang, Adrien Bercher, Yinan Dong, Dorri Halbertal, Vibhu Ravindran, Zijian Zhou, Mila Petrovic, Adrian Gozar, G. L. Carr, Qiang Li, Alexey Kuzmenko, Michael M. Fogler, D. N. Basov, Xu Du and Mengkun Liu
Nature nanotechnology (2023)
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Multiple antiferromagnetic phases and magnetic anisotropy in exfoliated CrBr3 multilayers
Fengrui Yao, Volodymyr Multian, Zhe Wang, Nicolas Ubrig, Jérémie Teyssier, Fan Wu, Enrico Giannini, Marco Gibertini, Ignacio Gutierrez Lezama and Alberto Morpurgo
Nature communications 14 1, 4969 (2023)
In twisted two-dimensional (2D) magnets, the stacking dependence of the magnetic exchange interaction can lead to regions of ferromagnetic and antiferromagnetic interlayer order, separated by non-collinear, skyrmion-like spin textures. Recent experimental searches for these textures have focused on …
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Thermal Polymorphism in CsCB11H12
Radovan Cerny, Matteo Brighi, Hui Wu, Wei Zhou, Mirjana Dimitrievska, Fabrizio Murgia, Valerio Gulino, Petra E. de Jongh, Benjamin A. Trump and Terrence J. Udovic
Molecules 28 5, 2296 (2023)
Thermal polymorphism in the alkali-metal salts incorporating the icosohedral monocarba-hydridoborate anion, CB11H12−, results in intriguing dynamical properties leading to superionic conductivity for the lightest alkali-metal analogues, LiCB11H12 and NaCB11H12. As such, these two have been the…
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Transport in Open Quantum Systems
Joao Dos Santos Ferreira
Thèse (2023)
In this thesis, I study the transport properties of driven out-of-equilibrium systems. This goal is achieved by employing a combination of analytic and numerical techniques to investigate low-dimensional fermionic chains affected by unitary interactions or dissipation. The latter allows for an…
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Explaining the effects of non-convergent MCMC in the training of Energy-Based Models
Elisabeth Agoritsas, Giovanni Catania and Aurélien Decelle
ICML’23: Proceedings of the 40th International Conference on Machine Learning, 322-336 (2023)
In this paper, we quantify the impact of using non-convergent Markov chains to train Energy-Based models (EBMs). In particular, we show analytically that EBMs trained with non-persistent short runs to estimate the gradient can perfectly reproduce a set of empirical statistics of the data, not at…
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Electronic structure of few-layer black phosphorus from μ-ARPES
Florian Margot, Simone Lisi, Irène Cucchi, Edoardo Cappelli, Andrew Scott Hunter, Ignacio Gutierrez Lezama, KeYuan Ma, Fabian von Rohr, Christophe Berthod, Francesco Petocchi, Samuel Poncé, Nicola Marzari, Marco Gibertini, Anna Tamai, Alberto Morpurgo and Felix Baumberger
Nano letters 23, 6433 (2023)
Black phosphorus (BP) stands out among two-dimensional (2D) semiconductors because of its high mobility and thickness dependent direct band gap. However, the quasiparticle band structure of ultrathin BP has remained inaccessible to experiment thus far. Here we use a recently developed laser-based…
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Reconciling scaling of the optical conductivity of cuprate superconductors with Planckian resistivity and specific heat
Bastien Michon, Christophe Berthod, Willem Rischau, Amirreza Ataei, Lu Chen, Seiki Komiya, Shimpei Ono, Louis Taillefer, Dirk Van Der Marel and Antoine Georges
Nature communications 14 1, 3033 (2023)
Materials tuned to a quantum critical point display universal scaling properties as a function of temperature T and frequency ω . A long-standing puzzle regarding cuprate superconductors has been the observed power-law dependence of optical conductivity with an exponent smaller than one, in…
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Determining spin-orbit coupling in graphene by quasiparticle interference imaging
Lihuan Sun, Louk Rademaker, Diego Mauro, Alessandro Scarfato, Arpad Pasztor, Ignacio Gutierrez Lezama, Zhen Wang, José Martinez Castro, Alberto Morpurgo and Christoph Renner
Nature communications 14 1, 3771 (2023)
Inducing and controlling spin-orbit coupling (SOC) in graphene is key to create topological states of matter, and for the realization of spintronic devices. Placing graphene onto a transition metal dichalcogenide is currently the most successful strategy to achieve this goal, but there is no…
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Strain Dependence of the Charge Density Wave Phase Transition
Vincent Pasquier
Thèse (2023)
Strain, which results from the deformation of a material, is used as a tuning parameter to study the charge density wave (CDW) phase in transition metal dichalcogenides (TMDs). We have developed two bending devices to apply uniaxial or biaxial strain to low-dimensional materials. Characterization…
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Layered metals as polarized transparent conductors
Carsten Putzke, Chunyu Guo, Vincent Plisson, Martin Kroner, Thibault Chervy, Matteo Simoni, Pim Wevers, Maja D. Bachmann, John R. Cooper, Antony Carrington, Naoki Kikugawa, Jennifer Fowlie, Stefano Gariglio, Andrew P. Mackenzie, Kenneth S. Burch, Ataç Îmamoğlu and Philip J. W. Moll
Nature communications 14 1, 3147, 1-7 (2023)
The quest to improve transparent conductors balances two key goals: increasing electrical conductivity and increasing optical transparency. To improve both simultaneously is hindered by the physical limitation that good metals with high electrical conductivity have large carrier densities that push …
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Fate of Quasiparticles at High Temperature in the Correlated Metal Sr2RuO4
Andrew Scott Hunter, S. Beck, Edoardo Cappelli, Florian Margot, Michael Straub, Yann Alexanian, Gianmarco Gatti, M. D. Watson, T. K. Kim, C. Cacho, N. C. Plumb, M. Shi, M. Radović, D. A. Sokolov, A. P. Mackenzie, M. Zingl, J. Mravlje, Antoine Georges, Felix Baumberger and Anna Tamai
Physical review letters 131, 236502 (2023)
We study the temperature evolution of quasiparticles in the correlated metal Sr$_2$RuO$_4$. Our angle resolved photoemission data show that quasiparticles persist up to temperatures above 200~K, far beyond the Fermi liquid regime. Extracting the quasiparticle self-energy we demonstrate that the…
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Tunable biaxial strain device for low-dimensional materials
Vincent Pasquier, Alessandro Scarfato, José Martinez Castro, Antoine Guipet and Christoph Renner
Review of scientific instruments 94 1, 013905 (2023)
Strain is attracting much interest as a mean to tune the properties of thin exfoliated two-dimensional materials and their heterostructures. Numerous devices to apply tunable uniaxial strain are proposed in the literature, but only few for biaxial strain, often with a trade-off between maximum…
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Band Gap Opening in Bilayer Graphene-CrCl3/CrBr3/CrI3 van der Waals Interfaces
Giulia Tenasini, David Soler Delgado, Zhe Wang, Fengrui Yao, Dumitru Dumcenco, Enrico Giannini, Kenji Watanabe, Takashi Taniguchi, Christian Moulsdale, Aitor Garcia-Ruiz, Vladimir I. Fal’ko, Ignacio Gutierrez Lezama and Alberto Morpurgo
Nano letters 22 16, 6760-6766 (2022)
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Nuclear and magnetic spin structure of the antiferromagnetic triangular lattice compound LiCrTe2 investigated by μ+SR, neutron and X-ray diffraction
E. Nocerino, Catherine Witteveen, S. Kobayashi, O. K. Forslund, N. Matsubara, A. Zubayer, F. Mazza, S. Kawaguchi, A. Hoshikawa, I. Umegaki, J. Sugiyama, K. Yoshimura, Y. Sassa, Fabian von Rohr and M. Månsson
Scientific reports 12 1, 21657 (2022)
Two-dimensional (2D) triangular lattice antiferromagnets (2D-TLA) often manifest intriguing physical and technological properties, due to the strong interplay between lattice geometry and electronic properties. The recently synthesized 2-dimensional transition metal dichalcogenide LiCrTe $$_2$$ 2 , …
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Dynamic magnetic crossover at the origin of the hidden-order in van der Waals antiferromagnet CrSBr
Sara Almudena Lopez Paz, Zurab Guguchia, Vladimir Y. Pomjakushin, Catherine Witteveen, Antonio Cervellino, Hubertus Luetkens, Nicola Casati, Alberto Morpurgo and Fabian von Rohr
Nature communications 13 1, 4745 (2022)
The van-der-Waals material CrSBr stands out as a promising two-dimensional magnet. Here, we report on its detailed magnetic and structural characteristics. We evidence that it undergoes a transition to an A-type antiferromagnetic state below T N ≈ 140 K with a pronounced…
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Evidence for isotropic s-wave superconductivity in high-entropy alloys
Casey K. W. Leung, Xiaofu Zhang, Fabian von Rohr, Rolf Lortz and Berthold Jäck
Scientific reports 12 1, 12773 (2022)
High-entropy alloys (HEA) form through the random arrangement of five or more chemical elements on a crystalline lattice. Despite the significant amount of resulting compositional disorder, a subset of HEAs enters a superconducting state below critical temperatures, $$T_{\text{c}}
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Optoelectronic Phenomena in 2D Materials and Heterostructures
Daniil Domaretskiy
Thèse, 148 (2022)
2-dimensional (2D) materials have stunned the scientific community and have triggered immense interest due to their unique optoelectronic properties. These properties strongly depend on the thickness of 2D layers and can be controlled by an externally applied voltage providing experimental…
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Light sources with bias tunable spectrum based on van der Waals interface transistors
Hugo Henck, Diego Mauro, Daniil Domaretskiy, Marc Philippi, Shahriar Memaran, Wenkai Zheng, Zhengguang Lu, Dmitry Shcherbakov, Chun Ning Lau, Dmitry Smirnov, Luis Balicas, Kenji Watanabe, Takashi Taniguchi, Vladimir I. Fal’ko, Ignacio Gutierrez Lezama, Nicolas Ubrig and Alberto Morpurgo
Nature communications 13 1, 3917 (2022)
Light-emitting electronic devices are ubiquitous in key areas of current technology, such as data communications, solid-state lighting, displays, and optical interconnects. Controlling the spectrum of the emitted light electrically, by simply acting on the device bias conditions, is an important…
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Resonant Inelastic X-Ray Scattering Study of Electron-Exciton Coupling in High-Tc Cuprates
Francesco Barantani, Michaël Tran, I. Madan, Itzik Kapon, Nimrod Bachar, T. c. Asmara, E. Paris, Y. Tseng, W. Zhang, Y. Hu, Enrico Giannini, G. Gu, T. p. Devereaux, Christophe Berthod, F. Carbone, T. Schmitt and Dirk Van Der Marel
Physical review. X 12 2, 021068 (2022)
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Metal to insulator transition at the surface of V2O3 thin films: An in-situ view
M. Caputo, J. Jandke, Edoardo Cappelli, S.K. Chaluvadi, E. Bonini Guedes, M. Naamneh, G. Vinai, J. Fujii, P. Torelli, I. Vobornik, A. Goldoni, P. Orgiani, Felix Baumberger, M. Radovic and G. Panaccione
Applied surface science 574, 151608 (2022)
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Electrostatically Driven Polarization Flop and Strain‐Induced Curvature in Free‐Standing Ferroelectric Superlattices
Yaqi Li, Edoardo Zatterin, Michele Conroy, Anastasiia Pylypets, Fedir Borodavka, Alexander Björling, Dirk J. Groenendijk, Edouard Lesne, Adam J. Clancy, Marios Hadjimichael, Demie Kepaptsoglou, Quentin M. Ramasse, Andrea Caviglia, Jiri Hlinka, Ursel Bangert, Steven J. Leake and Pavlo Zubko
Advanced materials, 2106826 (2022)
The combination of strain and electrostatic engineering in epitaxial heterostructures of ferroelectric oxides offers many possibilities for inducing new phases, complex polar topologies, and enhanced electrical properties. However, the dominant effect of substrate clamping can also limit the…
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Smooth velocity fields for tracking climate change
Iaroslav Gaponenko, Guillaume Thibaut Rohat, Stéphane Goyette, Patrycja Paruch and Jérôme Kasparian
Scientific reports 12 1, 2997 (2022)
Describing the spatial velocity of climate change is essential to assessing the challenge of natural and human systems to follow its pace by adapting or migrating sufficiently fast. We propose a fully-determined approach, “MATCH”, to calculate a realistic and continuous velocity field of any…
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Quasi 1D Electronic Transport in a 2D Magnetic Semiconductor
Fan Wu, Ignacio Gutierrez Lezama, Sara A. Lopéz‐Paz, Marco Gibertini, Kenji Watanabe, Takashi Taniguchi, Fabian Oliver Von Rohr, Nicolas Ubrig and Alberto Morpurgo
Advanced materials, 2109759 (2022)
We investigate electronic transport through exfoliated multilayers of CrSBr, a 2D semiconductor that is attracting attention because of its magnetic properties. We find an extremely pronounced anisotropy that manifests itself in qualitative and quantitative differences of all quantities measured…
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Electronic structure of the highly conductive perovskite oxide SrMoO3
Edoardo Cappelli, A. Hampel, A. Chikina, E. Bonini Guedes, Gianmarco Gatti, Andrew Scott Hunter, Julia Issing, N. Biskup, M. Varela, Cyrus E. Dreyer, Anna Tamai, Antoine Georges, F. Y. Bruno, M. Radovic and Felix Baumberger
Physical review materials 6, 075002 (2022)
We use angle-resolved photoemission to map the Fermi surface and quasiparticle dispersion of bulk-like thin films of SrMoO$_3$ grown by pulsed laser deposition. The electronic self-energy deduced from our data reveals weak to moderate correlations in SrMoO$_3$, consistent with our observation of…
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A Laser-ARPES View of the 2D Electron Systems at LaAlO3/SrTiO3 and Al/SrTiO3 Interfaces
Siobhan Mckeown Walker, Margherita Boselli, Emanuel A. Martínez, Stefano Gariglio, Flavio Y. Bruno and Felix Baumberger
Advanced electronic materials, 2101376 (2022)
We have measured the electronic structure of the two-dimensional electron system (2DES) found at the Al/SrTiO3 (Al/STO) and LaAlO3/SrTiO3 (LAO/STO) interfaces by means of laser angle resolved photoemission spectroscopy, taking advantage of the large photoelectron escape depth at low photon energy…
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Structural and electronic properties of SrCuO2+ δ thin films
Marios Hadjimichael, Adrien Waelchli, Bernat Mundet Bolos, Siobhan Mckeown Walker, Gabriele De Luca, Javier Herrero-Martín, Marta Gibert, Stefano Gariglio and Jean-Marc Triscone
APL materials 10 10, 101112 (2022)
The layered structure of superconducting cuprates is considered to be a key ingredient to achieve high superconducting transition temperatures. In this work, we investigate the possibility of doping the SrCuO 2 infinite-layer compound by inserting additional oxygen into its structure….
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Electrostatic solution of massless quenches in Luttinger liquids
Paola Ruggiero, Pasquale Calabrese, Thierry Giamarchi and Laura Foini
SciPost physics 13, 111 (2022)
The study of the non-equilibrium dynamics of many-body systems after a quantum quench received a considerable boost and a deep theoretical understanding from the path integral formulation in imaginary time. However, the celebrated problem of a quench in the Luttinger parameter of a one dimensional…
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Dynamical conductivity of disordered quantum chains
Shintaro Takayoshi and Thierry Giamarchi
The European physical journal. D, Atomic, molecular and optical physics 76, 213 (2022)
We study the transport properties of a one-dimensional quantum system with disorder. We numerically compute the frequency dependence of the conductivity of a fermionic chain with nearest-neighbor interaction and a random chemical potential by using the Chebyshev matrix product state (CheMPS)…
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Many-body parametric resonances in the driven sine-Gordon model
Izabella Lovas, Roberta Citro, Eugene Demler, Thierry Giamarchi, Michael Knap and Edmond Orignac
Physical review. B 106, 075426 (2022)
We study a quantum many-body variant of the parametric oscillator by investigating the driven sine-Gordon model with a modulated tunnel coupling via a semiclassical truncated Wigner approximation (TWA). We first analyze the parametric resonant regime for driving protocols that retain our model…
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Direct measurement of nonlocal interactions in the many-body localized phase
B. Chiaro, C. Neill, A. Bohrdt, Michele Filippone, F. Arute, K. Arya, R. Babbush, D. Bacon, J. Bardin, R. Barends, S. Boixo, D. Buell, B. Burkett, Y. Chen, Z. Chen, R. Collins, A. Dunsworth, E. Farhi, A. Fowler, B. Foxen, C. Gidney, M. Giustina, M. Harrigan, T. Huang, S. Isakov, E. Jeffrey, Z. Jiang, D. Kafri, K. Kechedzhi, J. Kelly, P. Klimov, A. Korotkov, F. Kostritsa, D. Landhuis, E. Lucero, J. McClean, X. Mi, A. Megrant, M. Mohseni, J. Mutus, M. McEwen, O. Naaman, M. Neeley, M. Niu, A. Petukhov, C. Quintana, N. Rubin, D. Sank, K. Satzinger, T. White, Z. Yao, P. Yeh, A. Zalcman, V. Smelyanskiy, H. Neven, S. Gopalakrishnan, Dmitry Abanin, M. Knap, J. Martinis and P. Roushan
Physical review research 4, 013148 (2022)
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Magnetic field tuning of valley population in the Weyl phase of Nd2Ir2O7
Itzik Kapon, Willem Rischau, Bastien Michon, Kai Wang, Bing Xu, Qiu Yang, Satoru Nakatsuji and Dirk Van Der Marel
Physical Review Research 4 2, 023056 (2022)
The frustrated magnet Nd 2 Ir 2 O7 , where strong correlations together with spin-orbit coupling play a crucial role, is predicted to be a Weyl semimetal and to host topological pairs of bulk Dirac-like valleys. Here we use an external magnetic field to manipulate the localized rare-earth 4f…
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Isotope tuning of the superconducting dome of strontium titanate
Willem Rischau, Dorota Pulmannova, Gernot Scheerer, Adrien Stucky, Enrico Giannini and Dirk Van Der Marel
Physical Review Research 4 1, 013019 (2022)
Doped strontium titanate SrTiO3 (STO) is one of the most dilute superconductors known today. The fact that superconductivity occurs at very low carrier concentrations is one of the two reasons that the pairing mechanism is not yet understood, the other being the role played by the proximity to a…
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Charge-Transfer and dd excitations in AgF2
Nimrod Bachar, Kacper Koteras, Jakub Gawraczynski, Waldemar Trzciński, Józef Paszula, Riccardo Piombo, Paolo Barone, Zoran Mazej, Giacomo Ghiringhelli, Abhishek Nag, Ke-Jin Zhou, José Lorenzana, Dirk Van Der Marel and Wojciech Grochala
Physical Review Research 4 2, 023108 (2022)
Charge-transfer insulators are the parent phase of a large group of today’s unconventional high-temperature superconductors. Here we study experimentally and theoretically the interband excitations of the charge-transfer insulator silver fluoride AgF2, which has been proposed as an excellent analog …
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A European Collaboration to Investigate Superconducting Magnets for Next Generation Heavy Ion Therapy
L. Rossi, A. Ballarino, D. Barna, E. Benedetto, C. Calzolaio, G. Ceruti, E. De Matteis, A. Echeandia, T. Ekelof, S. Farinon, E. Felcini, M. Gehring, G. Kirby, T. Lecrevisse, J. Lucas, S. Mariotto, J. Munilla, R. Musenich, A. Pampaloni, K. Pepitone, D. Perini, D. Popovic, M. Prioli, M. Pullia, L. Quettier, S. Sanfilippo, Carmine Senatore, E. Shabagin, M. Sorbi, M. Statera, D. Tommasini, F. Toral, R. Valente, D. Veres and M. Vieweg
IEEE transactions on applied superconductivity 32 4, 1-7 (2022)
Next generation ion therapy magnets both for gantry and for accelerator (synchrotron) are under investigation in a recently launched European collaboration that, in the frame of the European H2020 HITRIplus and I.FAST programmes, has obtained some funding for work packages on superconducting…
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Ultrathin Piezoelectric Resonators Based on Graphene and Free‐Standing Single‐Crystal BaTiO3
Martin Lee, Johannes R. Renshof, Kasper J. van Zeggeren, Maurits J. A. Houmes, Edouard Lesne, Makars Šiškins, Thierry C. van Thiel, Ruben H. Guis, Mark R. van Blankenstein, Gerard J. Verbiest, Andrea Caviglia, Herre S. J. van der Zant and Peter G. Steeneken
Advanced Materials 34 44, 2204630 (2022)
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Phase coherence in out-of-equilibrium supersolid states of ultracold dipolar atoms
P. Ilzhöfer, M. Sohmen, G. Durastante, C. Politi, A. Trautmann, G. Natale, Giacomo Arturo Maria Morpurgo, Thierry Giamarchi, L. Chomaz, M. J. Mark and F. Ferlaino
Nature physics 17, 356-361 (2021)
A supersolid is a counterintuitive phase of matter that combines the global phase coherence of a superfluid with a crystal-like self-modulation in space. Recently, such states have been experimentally realized using dipolar quantum gases. Here we inves- tigate the response of a dipolar supersolid…
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HTS Accelerator Magnet and Conductor Development in Europe
Lucio Rossi and Carmine Senatore
Instruments 5 8 (2021)
In view of the preparation for a post-LHC collider, in 2010 the high-energy physics (HEP) community started to discuss various options, including the use of HTS for very high-field dipoles. Therefore, a small program was begun in Europe that aimed at exploring the possibility of using HTS for…
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Strain tuning of interorbital correlations in LaVO3 thin films
Hugo Meley, Michaël Tran, Jérémie Teyssier, J. A. Krieger, T. Prokscha, A. Suter, Z. Salman, M. Viret, Dirk Van Der Marel and Stefano Gariglio
Physical Review. B, Condensed Matter 103 125112 (2021)
3d^2 vanadate perovskites exhibit an unusual phase diagram where the low temperature orbital and spin orders are strongly dependent upon the rare-earth cation size. Here, we demonstrate the delicate role of strain in epitaxial LaVO3 films by performing low-energy muon spin spectroscopy and…
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Crossover between distinct symmetries in solid solutions of rare earth nickelates
Jennifer Fowlie, Bernat Mundet Bolos, Constance Toulouse, Alexander Schober, Mael Guennou, Claribel Dominguez Ordonez, Marta Gibert, Duncan T. L. Alexander, Jens Kreisel and Jean-Marc Triscone
APL Materials 9 081119 (2021)
A strong coupling of the lattice to functional properties is observed in many transition metal oxide systems, such as the ABO3 perovskites. In the quest for tailor-made materials, it is essential to be able to control the structural properties of the compound(s) of interest. Here, thin film solid…
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Hydroborates as novel solid-state electrolytes
Arndt Remhof and Radovan Cerny
Crystallography in Materials Science, 265-290 (2021)
Hydroborates are a promising class of superionic conductors for lithium and sodium all-solid-state batteries. They combine high ionic conductivity with (electro-) chemical and thermal stability and favorable mechanical properties. In this chapter, we elucidate their conductivity mechanism based on…
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A methodology for the analysis of the three-dimensional mechanical behavior of a Nb3Sn superconducting accelerator magnet during a quench
José Ferradas Troitino, H Bajas, L Bianchi, B Castaldo, P Ferracin, M Guinchard, S Izquierdo, J V Lorenzo, F Mangiarotti, J C Perez, E Takala, G Vallone and Carmine Senatore
Superconductor Science and Technology 34 084003 (2021)
The fast thermal and electromagnetic transients that occur in a superconducting magnet in case of a quench have the potential of generating large mechanical stresses both in the superconducting coils and in the magnet structure. While the investigation of such quench loads should generally be…
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An optical study of the physics of the rare earth nickelates
Ivan Ardizzone
Thèse (2021)
We report the evolution of the lattice, electronic and magnetic structure of nickelates along the series using various optical spectroscopy techniques. The crystal structures from the highest to the lowest symmetry present in the phase diagram, the electronic structure and the different probable…
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Polymorphism of Calcium Decahydrido-closo-decaborate and Characterization of Its Hydrates
Mathias Jørgensen, Wei Zhou, Hui Wu, Terrence J. Udovic, Mark Paskevicius, Radovan Cerny and Torben R. Jensen
Inorganic Chemistry 60 15, 10943-10957 (2021)
Metal closo-borates and their derivatives have shown promise in several fields of application from cancer therapy to solidstate electrolytes partly owing to their stability in aqueous solutions and high thermal stability. We report the synthesis and structural analysis of α- and β-CaB10H10, which …
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Multiband charge density wave exposed in a transition metal dichalcogenide
Arpad Pasztor, Alessandro Scarfato, Marcello Spera, Felix Flicker, Céline Barreteau, Enrico Giannini, Jasper van Wezel and Christoph Renner
Nature communications 12 1, 6037 (2021)
In the presence of multiple bands, well-known electronic instabilities may acquire new complexity. While multiband superconductivity is the subject of extensive studies, the possibility of multiband charge density waves (CDWs) has been largely ignored so far. Here, combining energy dependent…
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Solitonic excitations in the Ising anisotropic chain BaCo2V2O8 under large transverse magnetic field
Quentin Faure, Shintaro Takayoshi, Béatrice Grenier, Sylvain Petit, Stéphane Raymond, Martin Boehm, Pascal Lejay, Thierry Giamarchi and Virginie Simonet
Physical review research 3, 043227 (2021)
We study the dynamics of the quasi-one-dimensional Ising-Heisenberg antiferromagnet BaCo2V2O8 under a transverse magnetic field. Combining inelastic neutron scattering experiments and theoretical analyses by field theories and numerical simulations, we mainly elucidate the structure of the spin…
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Degradation of domains with sequential field application
Nirvana Belen Caballero
Journal of statistical mechanics 2021, 103207 (2021)
Recent experiments show striking unexpected features when alter- nating square magnetic field pulses are applied to ferromagnetic samples: domains show area reduction and domains walls change their roughness. We explain these phenomena with a simple scalar-field model, using a numerical protocol…
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Electronic transport in submicrometric channels at the LaAlO3/SrTiO3 interface
Margherita Boselli, Gernot Scheerer, Michele Filippone, Weiwei Luo, Adrien Waelchli, Alexey Kuzmenko, Stefano Gariglio, Thierry Giamarchi and Jean-Marc Triscone
Physical review. B. 103, 075431 (2021)
Nanoscale channels realized at the conducting interface between LaAlO3 and SrTiO3 provide a perfect playground to explore the effect of dimensionality on the electronic properties of complex oxides. Here we compare the electric transport properties of devices realized using the atomic force…
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Probing the Hall Voltage in Synthetic Quantum Systems
Maximilian Buser, Sebastian Greschner, Ulrich Schollwöck and Thierry Giamarchi
Physical review letters 126, 030501 (2021)
In the context of experimental advances in the realization of artificial magnetic fields in quantum gases, we discuss feasible schemes to extend measurements of the Hall polarization to a study of the Hall voltage, allowing for direct comparison with solid state systems. Specifically, for the…
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In-Field Thermal Conductivity of Ag and Cu/Ag Ba1-xKxFe2As2 Composite Conductors
Marco Bonura, He Huang, Cong Liu, Yanwei Ma and Carmine Senatore
IEEE transactions on applied superconductivity 31 5, 7300105 (2021)
This work reports the longitudinal thermal conductivity, κ, of Ag- and Cu/Ag-sheathed Ba 1-x K x Fe 2 As 2 conductors. Our investigation has been carried out between 4 K and 80 K with magnetic fields up to 19 T. In the case of Ag-sheathed tapes, the thermal conductivity reaches maximum values of…
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Solution to the Quantum Symmetric Simple Exclusion Process: The Continuous Case
Denis Bernard and Zizhuo Tony Jin
Communications in Mathematical Physics 384 2, 1141-1185 (2021)
The quantum symmetric simple exclusion process (Q-SSEP) is a model for quantum stochastic dynamics of fermions hopping along the edges of a graph with Brownian noisy amplitudes and driven out-of-equilibrium by injection-extraction processes at a few vertices. We present a solution for the invariant …
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Roughness and dynamics of proliferating cell fronts as a probe of cell–cell interactions
Guillaume Rapin, Nirvana Belen Caballero, Iaroslav Gaponenko, Benedikt Ziegler, Audrey Rawleigh, Ermanno Moriggi, Thierry Giamarchi, Steven A. Brown and Patrycja Paruch
Scientific reports 11 1, 8869 (2021)
Juxtacellular interactions play an essential but still not fully understood role in both normal tissue development and tumour invasion. Using proliferating cell fronts as a model system, we explore the effects of cell–cell interactions on the geometry and dynamics of these one-dimensional…
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Magnetic order, disorder, and excitations under pressure in the Mott insulator Sr2IrO4
Xiang Li, S. E. Cooper, A. Krishnadas, A. de la Torre, R. S. Perry, Felix Baumberger, D. M. Silevitch, D. Hsieh, T. F. Rosenbaum and Yejun Feng
Physical review. B. 104 20, L201111 (2021)
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Creep Motion of Elastic Interfaces Driven in a Disordered Landscape
Ezequiel E. Ferrero, Laura Foini, Thierry Giamarchi, Alejandro B. Kolton and Alberto Rosso
Annual review of condensed matter physics 12, 111-134 (2021)
The thermally activated creep motion of an elastic interface weakly driven on a disordered landscape is one of the best examples of glassy universal dynamics. Its understanding has evolved over the past 30 years thanks to a fruitful interplay among elegant scaling arguments, sophisticated…
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Nucleation of Ergodicity by a Single Mobile Impurity in Supercooled Insulators
Ulrich Krause, Théo Pellegrin-Frachon, Piet W. Brouwer, Dmitry Abanin and Michele Filippone
Physical review letters 126, 030603 (2021)
We consider a disordered Hubbard model and show that, at sufficiently weak disorder, a single spin- down mobile impurity can thermalize an extensive initially localized system of spin-up particles. Thermalization is enabled by resonant processes that involve correlated hops of the impurity and…
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Interplay between transport and quantum coherences in free fermionic systems
Zizhuo Tony Jin, Tristan Gautié, Alexandre Krajenbrink, Paola Ruggiero and Takato Yoshimura
Journal of physics. A, Mathematical and theoretical 54, 404001 (2021)
We study the quench dynamics in free fermionic systems in the prototypical bipartitioning protocol obtained by joining two semi-infinite subsystems pre- pared in different states, aiming at understanding the interplay between quantum coherences in space in the initial state and transport…
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Tuning Ginzburg–Landau theory to quantitatively study thin ferromagnetic materials
Pamela C Guruciaga, Nirvana Belen Caballero, Vincent Jeudy, Javier Curiale and Sebastian Bustingorry
Journal of statistical mechanics 2021, 033211 (2021)
Along with experiments, numerical simulations are key to gaining insight into the underlying mechanisms governing domain wall motion in thin ferromagnetic systems. However, a direct comparison between numerical simula- tion of model systems and experimental results still represents a great…
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Magnetic properties of a quantum spin ladder in proximity to the isotropic limit
S. A. Zvyagin, A. N. Ponomaryov, M. Ozerov, E. Schulze, Y. Skourski, R. Beyer, T. Reimann, L. I. Zviagina, E. L. Green, J. Wosnitza, I. Sheikin, Pierre Bouillot, Thierry Giamarchi, J. L. Wikara, M. M. Turnbull and C. P. Landee
Physical review. B. 103, 205131 (2021)
We report on the synthesis, crystal structure, magnetic, thermodynamic, and electron-spin-resonance prop- erties of the coordination complex [Cu2(pz)3(4-HOpy)4](ClO4)4 (pz=pyrazine; 4-HOpy=4-hydroxypyridine)….
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Interband plasmon polaritons in magnetized charge-neutral graphene
T. M. Slipchenko, Jean-Marie Poumirol, Alexey Kuzmenko, A. Yu. Nikitin and L. Martín-Moreno
Communications physics 4 1, 110 (2021)
Studying the collective excitations in charge neutral graphene (CNG) has recently attracted a great interest because of unusual mechanisms of the charge carrier dynamics. The latter can play a crucial role for formation of recently observed in twisted bilayer CNG graphene plasmon polaritons (GPPs)…
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Ionic gate spectroscopy of 2D semiconductors
Ignacio Gutierrez Lezama, Nicolas Ubrig, Evgeniy Ponomarev and Alberto Morpurgo
Nature Reviews Physics (2021)
Reliable and precise measurements of the relative energy of band edges in 2D semiconductors are needed to determine band gaps and band offsets, as well as to establish the band diagram of devices and heterostructures. However, commonly employed techniques such as optical studies and scanning…
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Designing and controlling the properties of transition metal oxide quantum materials
Charles Ahn, Andrea Cavalleri, Antoine Georges, Sohrab Ismail-Beigi, Andrew J. Millis and Jean-Marc Triscone
Nature Materials (2021)
This Perspective addresses the design, creation, characterization and control of synthetic quantum materials with strong electronic correlations. We show how emerging synergies between theoretical/computational approaches and materials design/experimental probes are driving recent advances in the…
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Pressure-induced structural transitions triggering dimensional crossover in the lithium purple bronze Li0.9Mo6O17
Michaël Tran, Ana Akrap, Julien Levallois, Jérémie Teyssier, Pascal Schouwink, Céline Besnard, P. Lerch, J. W. Allen, M. Greenblatt and Dirk Van Der Marel
Physical Review. B, Condensed Matter 103 23 (2021)
At ambient pressure, lithium molybdenum purple bronze (Li0.9Mo6O17) is a quasi-one dimensionalsolid in which the anisotropic crystal structure and the linear dispersion of the underlying bandsproduced by electronic correlations possibly bring about a rare experimental realization of…
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Tantalates Transcend Titanates
Dirk Van Der Marel
Journal Club for Condensed Matter Physics (2021)
A discussion is presented of three recent papers describing a breakthrough in superconductivity in electron doped KTaO3 and SrTiO3. In their pristine (undoped) form these materials are band insulators with a 3 eV gap. At room temperature they have the cubic perovskite structure and both materials…
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Raman spectroscopic evidence for multiferroicity in rare earth nickelate single crystals
Ivan Ardizzone, Jérémie Teyssier, Iris Crassee, Alexey Kuzmenko, D. G. Mazzone, D. J. Gawryluk, M. Medarde and Dirk Van Der Marel
Physical Review Research 3 033007 (2021)
The rare earth nickelates RNiO3 are metallic at high temperatures and insulating and magnetically ordered at low temperatures. The low temperature phase has been predicted to be type II multiferroic, i.e., ferroelectricand magnetic order are coupled and occur simultaneously. Confirmation of those…
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Spectral weight of hole-doped cuprates across the pseudogap critical point
Bastien Michon, Alexey Kuzmenko, Michaël Tran, Benjamin Robert Mc Elfresh, S. Komiya, S. Ono, S. Uchida and Dirk Van Der Marel
Physical review research 3 4, 043125 (2021)
One of the most widely discussed features of the cuprate high-Tc superconductors is the presence of a pseudogap in the normal state. Recent transport and specific heat measurements have revealed an abrupt transition at the pseudogap critical point, denoted p∗, characterized by a drop in carrier…
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Powder diffraction
James A. Kaduk, Simon J. L. Billinge, Robert E. Dinnebier, Nathan Henderson, Ian Madsen, Radovan Cerny, Matteo Leoni, Luca Lutterotti, Seema Thakral and Daniel Chateigner
Nature reviews methods primers 1 1, 77 (2021)
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Nanoinfrared Characterization of Bilayer Graphene Conductivity under Dual-Gate Tuning
Weiwei Luo, Alexey Kuzmenko, Jialin Qi, Ni Zhang, Wei Wu, Mengxin Ren, Xinzheng Zhang, Wei Cai and Jingjun Xu
Nano letters 21 12, 5151-5157 (2021)
Dual-gate tuning on two-dimensional (2D) heterostructures can provide independent control of the carrier concentration and interlayer electrostatic potential, yielding novel electronic and optical properties. In this paper, by utilizing monolayer graphene as both the top gate and a plasmon…
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Enhanced Room-Temperature Ionic Conductivity of NaCB 11 H 12 via High-Energy Mechanical Milling
Fabrizio Murgia, Matteo Brighi, Laura Piveteau, Claudia E. Avalos, Valerio Gulino, Marc C. Nierstenhöfer, Peter Ngene, Petra de Jongh and Radovan Cerny
ACS applied materials & interfaces 13 51, 61346-61356 (2021)
The body-centered cubic (bcc) polymorph of NaCB11H12 has been stabilized at room temperature by highenergy mechanical milling. Temperature-dependent electrochemical impedance spectroscopy shows an optimum at 45-min milling time, leading to an rt conductivity of 4 mS cm−1. Mechanical milling…
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Electronic coupling in nickelate-based superlattices
Claribel Dominguez Ordonez
Thèse, 122 (2021)
We discussed a particularly interesting interfacial effect-a coupling due to a phase boundary cost-that can be used to achieve fine control over the electronic properties of artificially-layered materials. The artificial model system, presented in this thesis, uses SmNiO3 and NdNiO3-two compounds…
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Skyrmion-(Anti)Vortex Coupling in a Chiral Magnet-Superconductor Heterostructure
A. P. Petrović, M. Raju, X. Y. Tee, A. Louat, Ivan Maggio-Aprile, R. M. Menezes, M. J. Wyszyński, N. K. Duong, M. Reznikov, Christoph Renner, M. V. Milošević and C. Panagopoulos
Physical Review Letters 126 117205 (2021)
We report experimental coupling of chiral magnetism and superconductivity in [IrFeCoPt]/Nb heterostructures. The stray field of skyrmions with radius ≈50 nm is sufficient to nucleate antivortices in a 25 nm Nb film, with unique signatures in the magnetization, critical current, and flux dynamics, …
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Nido‐Hydroborate‐Based Electrolytes for All‐Solid‐State Lithium Batteries
SeyedHosein Payandeh, Daniel Rentsch, Zbigniew Łodziana, Ryo Asakura, Radovan Bigler, Radovan Cerny, Corsin Battaglia and Arndt Remhof
Advanced Functional Materials 31 18, 2010046 (2021)
Hydroborate‐based solid electrolytes have recently been successfully employed in high voltage, room temperature all‐solid‐state sodium batteries. The transfer to analogous lithium systems has failed up to now due to the lower conductivity of the corresponding lithium compounds and their high…
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Development and large volume production of extremely high current density YBa2Cu3O7 superconducting wires for fusion
A. Molodyk, S. Samoilenkov, A. Markelov, P. Degtyarenko, S. Lee, V. Petrykin, M. Gaifullin, A. Mankevich, A. Vavilov, B. Sorbom, J. Cheng, S. Garberg, L. Kesler, Z. Hartwig, S. Gavrilkin, A. Tsvetkov, T. Okada, S. Awaji, D. Abraimov, A. Francis, G. Bradford, D. Larbalestier, Carmine Senatore, Marco Bonura, A. E. Pantoja, S. C. Wimbush, N. M. Strickland and A. Vasiliev
Scientific Reports 11 2084 (2021)
The fusion power density produced in a tokamak is proportional to its magnetic field strength to the fourth power. Second-generation high temperature superconductor (2G HTS) wires demonstrate remarkable engineering current density (averaged over the full wire), JE, at very high magnetic fields,…
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Room-Temperature Solid-State Lithium-Ion Battery Using a LiBH4–MgO Composite Electrolyte
Valerio Gulino, Matteo Brighi, Fabrizio Murgia, Peter Ngene, Radovan de Jongh, Radovan Cerny and Marcello Baricco
ACS Applied Energy Materials 4 2, 1228-1236 (2021)
LiBH4 has been widely studied as a solid-state electrolyte in Li-ion batteries working at 120 °C due to the low ionic conductivity at room temperature. In this work, by mixing with MgO, the Li-ion conductivity of LiBH4 has been improved. The optimum composition of the mixture is 53 v/v % of MgO,…
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Quenchable Porous High-Temperature Polymorph of Sodium Imidazolate, NaIm
Sanja Burazer, Koen Robeyns, Laure Guenee, Gregor Mali, Fabrice Morelle, Voraksmy Ban, Teodoro Klaser, Radovan Filinchuk, Radovan Cerny and Jasminka Popović
Crystal Growth & Design 21 2, 770-778 (2021)
The novel high-temperature polymorph of sodium imidazolate reported in this paper was discovered in the mechanochemical reaction of NaIm with NaBH4 and later prepared directly by thermal treatment of the room-temperature polymorph of NaIm. Solid-state NMR was used for initial elucidation of…
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Theory of cross quantum capacitance
Christophe Berthod, Haijing Zhang, Alberto Morpurgo and Thierry Giamarchi
Physical Review Research 3 4, 043036 (2021)
Impressive progress in the control of atomically thin crystals is now enabling the realization of gated structures in which two electrodes are separated by atomic scale distances. The electrical capacitance of these structures is determined by phenomena that are not relevant in capacitors with…
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Hydrodynamical description for magneto-transport in the strange metal phase of Bi-2201
Andrea Amoretti, Martina Meinero, Daniel K. Brattan, Federico Caglieris, Enrico Giannini, Marco Affronte, Christian Hess, Bernd Buechner, Nicodemo Magnoli and Marina Putti
Physical review research 2 2, 023387 (2020)
High-temperature superconductors are strongly coupled systems which present a complicated phase diagram with many coexisting phases. This makes it difficult to understand the mechanism which generates their singular transport properties. Hydrodynamics, which mostly relies on the symmetries of the…
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Thermodynamic Behavior of Rare Earth Pyrochlores
Alexandra Turrini
Thèse (2020)
A large part of the field of highly frustrated magnetism has been devoted to studying the phases and excitations in the rare earth titanates. In this thesis, two of these materials, Ho2Ti2O7 and Tb2Ti2O7, have been investigated in terms of changes in their magnetic phase and properties of their…
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High-field superconductivity in C-doped MgB2 bulk samples prepared by a rapid synthesis route
Davide Matera, Marco Bonura, Radovan Cerny, Siobhan Mckeown Walker, Florin Buta, D. LeBoeuf, X. Chaud, Enrico Giannini and Carmine Senatore
Scientific Reports 10 17656 (2020)
The upper critical field sets the thermodynamic limit to superconductivity. A big gap is present between the upper-critical-field values measured in MgB2 polycrystalline bulk superconductors and those of thin films, where values as high as ~ 50 T have been achieved at 4.2 K. Filling this gap…
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Translucent in air and iridescent in water: structural analysis of a salamander egg sac
Aleksandra Zabuga, Marcelle Arrigo, Jérémie Teyssier, Sébastien R. Mouchet, Kanto Nishikawa, Masafumi Matsui, Miguel Vences and Michel C. Milinkovitch
Soft Matter 16 7, 1714-1721 (2020)
Females of some Asian salamanders of the genus Hynobius deposit in streams their eggs embedded in a translucent envelope called an ‘egg sac’. The edges of the envelope exhibit a spectacular blue-to-yellow iridescent glow, which instantaneously disappears when the sac is removed from water. First, …
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Nido-Borate/Closo-Borate Mixed-Anion Electrolytes for All-Solid-State Batteries
SeyedHosein Payandeh, Ryo Asakura, Petroula Avramidou, Daniel Rentsch, Zbigniew Łodziana, Radovan Cerny, Arndt Remhof and Corsin Battaglia
Chemistry of Materials 32 3, 1101-1110 (2020)
Closo-borates and carba-closo-borates recently emerged as a promising class of solid electrolytes for all-solid-state batteries but are too expensive. Here, we introduce NaB11H14nido-borates as a new building block for solid electrolytes that can be synthesized via a cost-effective low-temperature…
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Low-temperature monoclinic layer stacking in atomically thin CrI3 crystals
Nicolas Ubrig, Zhe Wang, Jérémie Teyssier, Takashi Taniguchi, Kenji Watanabe, Enrico Giannini, Alberto Morpurgo and Marco Gibertini
2D Materials 7 1, 015007 (2020)
Chromium triiodide, CrI3, is emerging as a promising magnetic two-dimensional semiconductor where spins are ferromagnetically aligned within a single layer. Potential applications in spintronics arise from an antiferromagnetic ordering between adjacent layers that gives rise to spin filtering and a …
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Synthetic Semimetals with van der Waals Interfaces
Bojja Aditya Reddy, Evgeniy Ponomarev, Ignacio Gutierrez Lezama, Nicolas Ubrig, Céline Barreteau, Enrico Giannini and Alberto Morpurgo
Nano Letters 20 2, 1322-1328 (2020)
The assembly of suitably designed van der Waals (vdW) heterostructures represents a new approach to produce artificial systems with engineered electronic properties. Here, we apply this strategy to realize synthetic semimetals based on vdW interfaces formed by two different semiconductors. Guided…
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Understanding Superionic Conductivity in Lithium and Sodium Salts of Weakly Coordinating Closo-Hexahalocarbaborate Anions
Mathias Jørgensen, Patrick T. Shea, Anton W. Tomich, Joel B. Varley, Marnik Bercx, Radovan Lovera, Radovan Cerny, Wei Zhou, Terrence J. Udovic, Vincent Lavallo, Torben R. Jensen, Brandon C. Wood and Vitalie Stavila
Chemistry of Materials 32 4, 1475-1487 (2020)
Solid-state ion conductors based on closo-polyborate anions combine high ionic conductivity with a rich array of tunable properties. Cation mobility in these systems is intimately related to the strength of the interaction with the neighboring anionic network and the energy for reorganizing the…
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Observation of flat bands in twisted bilayer graphene
Simone Lisi, Xiaobo Lu, Tjerk Benschop, Tobias A. de Jong, Petr Stepanov, Jose R. Duran, Florian Margot, Irène Cucchi, Edoardo Cappelli, Andrew Scott Hunter, Anna Tamai, Viktor Kandyba, Alessio Giampietri, Alexei Barinov, Johannes Jobst, Vincent Stalman, Maarten Leeuwenhoek, Kenji Watanabe, Takashi Taniguchi, Louk Rademaker, Sense Jan van der Molen, Milan P. Allan, Dmitri K. Efetov and Felix Baumberger
Nature physics 17 2, 189-193 (2020)
We combine different imaging techniques and angle-resolved photoemission with simultaneous real- and momentum-space resolution (nano-ARPES) to directly map the band dispersion in twisted bilayer graphene devices near charge neutrality. Our experiments reveal large areas with a homogeneous twist…
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Direct comparison of ARPES, STM, and quantum oscillation data for band structure determination in Sr2RhO4
I. Battisti, W. O. Tromp, Sara Ricco, R. S. Perry, A. P. Mackenzie, Anna Tamai, Felix Baumberger and M. P. Allan
npj Quantum Materials 5 1, 91 (2020)
Discrepancies in the low-energy quasiparticle dispersion extracted from angle-resolved photoemission, scanning tunneling spectroscopy, and quantum oscillation data are common and have long haunted the field of quantum matter physics. Here, we directly test the consistency of results from these…
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Length scales of interfacial coupling between metal and insulator phases in oxides
Claribel Dominguez Ordonez, Alexandru B. Georgescu, Bernat Mundet Bolos, Yajun Zhang, Jennifer Fowlie, Alain Mercy, Adrien Waelchli, Sara Catalano, Duncan T. L. Alexander, Philippe Ghosez, Antoine Georges, Andrew J. Millis, Marta Gibert Gutierrez and Jean-Marc Triscone
Nature materials 19 11, 1182-1187 (2020)
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Full Control of Polarization in Ferroelectric Thin Films Using Growth Temperature to Modulate Defects
Christian Weymann, Céline Lichtensteiger, Stéphanie Fernandez‐Peña, Aaron B. Naden, Liv R. Dedon, Lane W. Martin, Jean-Marc Triscone and Patrycja Paruch
Advanced Electronic Materials 6 12, 2000852 (2020)
Deterministic control of the intrinsic polarization state of ferroelectric thin films is essential for device applications. Independently of the well-established role of electrostatic boundary conditions and epitaxial strain, the importance of growth temperature as a tool to stabilize a target…
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Improved thin film growth using Slow Kinetics Intermittent Sputtering
Christian Weymann, Céline Lichtensteiger, Stéphanie Fernandez-Peña, Rohini Kumara Cordero Eduards and Patrycja Paruch
Applied Surface Science 516 146077 (2020)
Radio-frequency off-axis magnetron sputtering is a well established technique to produce high quality epitaxial thin films of complex oxides. It has been successfully used for over two decades to grow thin films, superlattices and even solid solutions. The main drawback is the common lack of in…
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Generic transport formula for a system driven by Markovian reservoirs
Zizhuo Tony Jin, Michele Filippone and Thierry Giamarchi
Physical Review. B, Condensed Matter 102 205131 (2020)
We present a generic, compact formula for the current flowing in interacting and noninteracting systems which are driven out of equilibrium by biased reservoirs described by Lindblad jump operators. We show that, in the limit of high temperature and chemical potential, our formula is equivalent to…
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Optical properties of LaNiO3 films tuned from compressive to tensile strain
Ivan Ardizzone, M. Zingl, Jérémie Teyssier, H. U. R. Strand, Oleg Peil, Jennifer Fowlie, A. B. Georgescu, Sara Catalano, Nimrod Bachar, Alexey Kuzmenko, Marta Gibert Gutierrez, Jean-Marc Triscone, Antoine Georges and Dirk Van Der Marel
Physical Review. B, Condensed Matter 102 15, 155148 (2020)
Materials with strong electronic correlations host remarkable — and technologically relevant — phenomena such as magnetism, superconductivity and metal-insulator transitions. Harnessing and controlling these effects is a major challenge, on which key advances are being made through lattice and…
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Manifestation of structural Higgs and Goldstone modes in the hexagonal manganites
Quintin N. Meier, Adrien Stucky, Jérémie Teyssier, Sinéad M. Griffin, Dirk Van Der Marel and Nicola A. Spaldin
Physical Review. B, Condensed Matter 102 014102 (2020)
Structural phase transitions described by Mexican hat potentials should in principle exhibit aspects of Higgs and Goldstone physics. Here, we investigate the relationship between the phonons that soften at such structural phase transitions and the Higgs- and Goldstone-boson analogues associated…
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Ferroelectricity, Superconductivity, and SrTiO3—Passions of K.A. Müller
Gernot Scheerer, Margherita Boselli, Dorota Pulmannova, Willem Rischau, Adrien Waelchli, Stefano Gariglio, Enrico Giannini, Dirk Van Der Marel and Jean-Marc Triscone
Condensed Matter 5 4, 60 (2020)
SrTiO3 is an insulating material which, using chemical doping, pressure, strain or isotope substitution, can be turned into a ferroelectric material or into a superconductor. The material itself, and the two aforementioned phenomena, have been subjects of intensive research of Karl Alex Müller and …
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Unconventional free charge in the correlated semimetal Nd2Ir2O7
Kai Wang, B. Xu, Willem Rischau, Nimrod Bachar, Bastien Michon, Jérémie Teyssier, Y. Qiu, T. Ohtsuki, Bing Cheng, N. P. Armitage, S. Nakatsuji and Dirk Van Der Marel
Nature Physics 16 12, 1194-1198 (2020)
Nd2Ir2O7 is a correlated semimetal with the pyrochlore structure, in which competing spin-orbit coupling and electron-electron interactions are believed to induce a time-reversal symmetry broken Weyl semimetal phase characterized by pairs of topologically protected Dirac points at the Fermi energy. …
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Giant anomalous Hall effect in quasi-two-dimensional layered antiferromagnet Co1/3NbS2
Giulia Tenasini, Edoardo Martino, Nicolas Ubrig, Nirmal J. Ghimire, Helmuth Berger, Oksana Zaharko, Fengcheng Wu, J. F. Mitchell, Ivar Martin, László Forró and Alberto Morpurgo
Physical Review Research 2 2, 023051 (2020)
The discovery of the anomalous Hall effect (AHE) in bulk metallic antiferromagnets (AFMs) motivates the search of the same phenomenon in two-dimensional (2D) systems, where a quantized anomalous Hall conductance can, in principle, be observed. Here we present experiments on microfabricated devices…
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Design of van der Waals interfaces for broad-spectrum optoelectronics
Nicolas Ubrig, Evgeniy Ponomarev, Johanna Zultak, Daniil Domaretskiy, Viktor Zólyomi, Daniel Terry, James Howarth, Ignacio Gutierrez Lezama, Alexander Zhukov, Zakhar R. Kudrynskyi, Zakhar D. Kovalyuk, Amalia Patané, Takashi Taniguchi, Kenji Watanabe, Roman V. Gorbachev, Vladimir I. Fal'ko and Alberto Morpurgo
Nature Materials (2020)
Van der Waals (vdW) materials offer new ways to assemble artificial electronic media with properties controlled at the design stage, by combining atomically defined layers into interfaces and heterostructures. Their potential for optoelectronics stems from the possibility to tailor the spectral…
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Coupling Lattice Instabilities Across the Interface in Ultrathin Oxide Heterostructures
Thierry C. van Thiel, Jennifer Fowlie, Carmine Autieri, Nicola Manca, Makars Šiškins, Dmytro Afanasiev, Stefano Gariglio and Andrea Caviglia
ACS Materials Letters 2 4, 389-394 (2020)
Oxide heterointerfaces constitute a rich platform for realizing novel functionalities in condensed matter. A key aspect is the strong link between structural and electronic properties, which can be modified by interfacing materials with distinct lattice symmetries. Here, we determine the effect of…
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Flipping exciton angular momentum with chiral phonons in MoSe2/WSe2 heterobilayers
A Delhomme, D Vaclavkova, A Slobodeniuk, M Orlita, M Potemski, D M Basko, K Watanabe, T Taniguchi, Diego Mauro, Céline Barreteau, Enrico Giannini, Alberto Morpurgo, Nicolas Ubrig and C Faugeras
2D Materials 7 041002 (2020)
Optical selection rules in monolayers of transition metal dichalcogenides and of their heterostructures are determined by the conservation of the z-component of the total angular momentum—J Z = L Z +S Z – associated with the C3 rotational lattice symmetry which assumes half integer values…
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Optical properties of 5d transition metal oxides
Kai Wang
Thèse (2020)
The strong correlated electronic materials we focused on this thesis are 5d transition metal oxides. The interplay of strong spin-orbit coupling (SOC) and intermediate on-site Coulomb repulsion U can give rise to the novel collective phenomenon. During this Ph.D., I focused on two iridate families…
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The Crystal Chemistry of Inorganic Hydroborates
Radovan Cerny, Matteo Brighi and Fabrizio Murgia
Chemistry — An International Journal 2 4, 805-826 (2020)
The crystal structures of inorganic hydroborates (salts and coordination compounds with anions containing hydrogen bonded to boron) except for the simplest anion, borohydride BH4−, are analyzed regarding their structural prototypes found in the inorganic databases such as Pearson’s Crystal Data…
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Role of point and line defects on the electronic structure of LaAlO3/SrTiO3 interfaces
Alexandre Gloter, Giulio Tieri, Danfeng Li, Marco Caputo, Vladimir N. Strocov, Odile Stéphan, Jean-Marc Triscone and Stefano Gariglio
APL Materials 8 4, 041103 (2020)
Realization of heterostructures containing multiple two-dimensional electron liquids requires a fine control of the fabrication process. Here, we report a structural and spectroscopy study of LaAlO3/SrTiO3/LaAlO3 trilayers grown on the SrTiO3 substrate by pulsed-laser deposition. Scanning…
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Artificial quantum confinement in LaAlO3/SrTiO3 heterostructures
M. Caputo, Margherita Boselli, A. Filippetti, S. Lemal, Danfeng Li, A. Chikina, C. Cancellieri, T. Schmitt, Jean-Marc Triscone, P. Ghosez, Stefano Gariglio and V. N. Strocov
Physical Review Materials 4 3, 035001 (2020)
Heterostructures of transition metal oxides perovskites represent an ideal platform to explore exotic phenomena involving the complex interplay between the spin, charge, orbital and lattice degrees of freedom available in these compounds. At the interface between such materials, this interplay can…
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The mechanism of Mg2+ conduction in ammine magnesium borohydride promoted by a neutral molecule
Yigang Yan, Wilke Dononelli, Mathias Jørgensen, Jakob B. Grinderslev, Young-Su Lee, Radovan Cho, Radovan Cerny, Bjørk Hammer and Torben R. Jensen
Physical Chemistry Chemical Physics 22 17, 9204-9209 (2020)
Light weight and cheap electrolytes with fast multi-valent ion conductivity can pave the way for future high-energy density solid-state batteries, beyond the lithium-ion battery. Here we present the mechanism of Mg-ion conductivity of monoammine magnesium borohydrides, Mg(BH4)2·NH3. Density…
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Bulk and Surface Electronic Structure of the Dual-Topology Semimetal Pt2HgSe3
Irène Cucchi, A. Marrazzo, Edoardo Cappelli, Sara Ricco, F. Y. Bruno, Simone Lisi, M. Hoesch, T. K. Kim, C. Cacho, Céline Besnard, Enrico Giannini, N. Marzari, Marco Gibertini, Felix Baumberger and Anna Tamai
Physical Review Letters 124 106402 (2020)
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Interplay between cold densification and malic acid addition (C4H6O5) for the fabrication of near-isotropic MgB2 conductors for magnet application
Md. Shahriar A. Hossain, Carmine Senatore, Yusuke Yamauchi, Mislav Mustapić, Daniel Gajda, Dipak Patel, Aslam Khan, Jung Ho Kim, Andrzej J Morawski and René-Louis Flukiger
Journal of Magnesium and Alloys 8 2, 493-498 (2020)
The effect of cold high pressure densification (CHPD) on anisotropy of the critical current density (Jc) in « in situ » single core binary and alloyed MgB2 tapes has been determined as a function of temperatures at 4.2 K, 20 K and 25 K as well as at applied magnetic fields up to 19 T. The…
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On the mechanical behavior of a Nb3Sn superconducting coil during a quench: Two-dimensional finite element analysis of a quench heater protected magnet
José Ferradas Troitino, G. Ambrosio, H. Bajas, L. Brouwer, P. Ferracin, S. Izquierdo Bermudez, J.V. Lorenzo Gomez, F.J. Mangiarotti, J.C. Perez, E. Ravaioli, E. Tapani Taakala, G. Vallone and Carmine Senatore
Cryogenics 106 103054 (2020)
New high-field accelerator magnets based on Nb3Sn superconductors are pushing the boundaries of magnet design and quench protection towards new limits. While their large stored energies and current densities result in a very challenging scenario for magnet protection, their great electromagnetic…
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Significant reduction of critical current anisotropy in malic acid treated MgB2 tapes
Md. Shahriar A. Hossain, Mislav Mustapić, Daniel Gajda, Carmine Senatore, Dipak Patel, Yusuke Yamauchi, Mahboobeh Shahbazi and René-Louis Flukiger
Journal of Magnetism and Magnetic Materials 497 166046 (2020)
The anisotropy of the critical current density, the n-factor and the irreversibility field of mono-core in-situ MgB2 tapes have been studied at various magnetic field orientations and temperatures. Undoped as well as silicon carbide (SiC) and malic acid (C4H6O5) added tapes were studied. The…
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Multi-frequency Shubnikov-de Haas oscillations in topological semimetal Pt2HgSe3
Diego Mauro, Hugo Henck, Marco Gibertini, Michele Filippone, Enrico Giannini, Ignacio Gutierrez Lezama and Alberto Morpurgo
2D Materials 7 025042 (2020)
Monolayer jacutingaite (Pt2HgSe3) has been recently identified as a candidate quantum spin Hall system with a 0.5 eV band gap, but no transport measurements have been performed so far on this material, neither in monolayer nor in the bulk. By using a dedicated high-pressure technique, we grow…
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Periodicity of superconducting shape resonances in thin films
Davide Filippo Valentinis and Christophe Berthod
Physical Review. B, Condensed Matter 102 054518 (2020)
The pairing temperature of superconducting thin films is expected to display, within the Bardeen–Cooper–Schrieffer theory, oscillations as a function of the film thickness. We show that the pattern of these oscillations switches between two different periodicities at a density-dependent value…
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Topological charge pumping of bound bosonic pairs
Sebastian Greschner, Suman Mondal and Tapan Mishra
Physical Review. A 101 053630 (2020)
Experiments with bosonic atoms in optical superlattices allow for the interesting possibility to study the adiabatic quantized pumping of bosonic atoms in the presence of interactions. We investigate this exotic phenomenon for bound bosonic pairs in the paradigmatic Su-Schrieffer-Heeger model where …
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Dynamic Manipulation in Piezoresponse Force Microscopy: Creating Nonequilibrium Phases with Large Electromechanical Response
Kyle P. Kelley, Yao Ren, Anna N. Morozovska, Eugene A. Eliseev, Yoshitaka Ehara, Hiroshi Funakubo, Thierry Giamarchi, Nina Balke, Rama K. Vasudevan, Ye Cao, Stephen Jesse and Sergei V. Kalinin
ACS Nano 14 8, 10569-10577 (2020)
Domain walls and topological defects in ferroelectric materials have emerged as a powerful tool for functional electronic devices including memory and logic. Similarly, wall interactions and dynamics underpin a broad range of mesoscale phenomena ranging from giant electromechanical responses to…
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Phase-Coherent Dynamics of Quantum Devices with Local Interactions
Michele Filippone, Arthur Marguerite, Karyn Le Hur, Gwendal Fève and Christophe Mora
Entropy 22 8, 847 (2020)
This review illustrates how Local Fermi Liquid (LFL) theories describe the strongly correlated and coherent low-energy dynamics of quantum dot devices. This approach consists in an effective elastic scattering theory, accounting exactly for strong correlations. Here, we focus on the mesoscopic…
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Ballistic-to-diffusive transition in spin chains with broken integrability
João S. Ferreira and Michele Filippone
Physical Review. B, Condensed Matter 102 184304 (2020)
We study the ballistic-to-diffusive transition induced by the weak breaking of integrability in a boundary-driven XXZ spin chain. Studying the evolution of the spin current density Js as a function of the system size L, we show that, accounting for boundary effects, the transition has a nontrivial…
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Deconfining Disordered Phase in Two-Dimensional Quantum Link Models
Lorenzo Cardarelli, Sebastian Greschner and Luis Santos
Physical Review Letters 124 123601 (2020)
We explore the ground-state physics of two-dimensional spin-1/2 U(1) quantum link models, one of the simplest nontrivial lattice gauge theories with fermionic matter within experimental reach for quantum simulations. Whereas in the large mass limit we observe Neél-like vortex-antivortex and…
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Spin transport in a one-dimensional quantum wire
Anne-Maria Visuri, M. Lebrat, S. Häusler, L. Corman and Thierry Giamarchi
Physical Review Research 2 023062 (2020)
We analyze the spin transport through a finite-size one-dimensional interacting wire connected to noninteracting leads. By combining renormalization-group arguments with other analytic considerations such as the memory function technique and instanton tunneling, we find the temperature dependence…
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Insight into the Charge Density Wave Gap from Contrast Inversion in Topographic STM Images
Marcello Spera, Alessandro Scarfato, Arpad Pasztor, Enrico Giannini, D. R. Bowler and Christoph Renner
Physical Review Letters 125 267603 (2020)
Charge density waves (CDWs) are understood in great detail in one dimension, but they remain largely enigmatic in two-dimensional systems. In particular, numerous aspects of the associated energy gap and the formation mechanism are not fully understood. Two long-standing riddles are the amplitude…
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Equilibration of quantum cat states
Zizhuo Tony Jin
SciPost physics 9 1, 004 (2020)
We study the equilibration properties of isolated ergodic quantum systems initially prepared in a cat state, i.e a macroscopic quantum superposition of states. Our main result consists in showing that, even though decoherence is at work in the mean, there exists a remnant of the initial quantum…
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Phase separation in the vicinity of Fermi surface hot spots
T. Jaouen, B. Hildebrand, M.-L. Mottas, M. Di Giovannantonio, P. Ruffieux, M. Rumo, C. W. Nicholson, E. Razzoli, Céline Barreteau, Alberto Ubaldini, Enrico Giannini, F. Vanini, H. Beck, C. Monney and P. Aebi
Physical review. B 100 7, 075152 (2019)
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Semimetal-to-semiconductor transition and charge-density-wave suppression in 1T−TiSe2-xSx single crystals
M.-L. Mottas, T. Jaouen, B. Hildebrand, M. Rumo, F. Vanini, E. Razzoli, Enrico Giannini, Céline Barreteau, D. R. Bowler, C. Monney, H. Beck and P. Aebi
Physical review. B 99 15, 155103 (2019)
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Open source standalone relative humidity controller for laboratory applications
Iaroslav Gaponenko, Loïc Musy, Sébastien Muller and Patrycja Paruch
Engineering research express 1 2, 025042 (2019)
From the survival of biological systems to the surface electrochemistry of materials, ambient and surface water plays a key role, and understanding its contribution is essential to describe the observed behaviours fully. Thus, precise measurement and control of relative humidity are essential in…
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How flow reduction influences the intracranial aneurysm occlusion: a prospective 4D phase-contrast MRI study
Olivier Brina, Pierre Bouillot, Philippe Reymond, Anna Siri Naemi Luthman, Corrado Santarosa, Mohamed Fahrat, Karl-Olof Lövblad, Paolo Machi, Bénédicte Delattre, Vitor Mendes Pereira and Maria Isabel Vargas Gomez
American Journal of Neuroradiology (2019)
Flow-diverter stents are widely used for the treatment of wide-neck intracranial aneurysms. Various parameters may influence intracranial aneurysm thrombosis, including the flow reduction induced by flow-diverter stent implantation, which is assumed to play a leading role. However, its actual…
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Energy-dependent spatial texturing of charge order in 1T-CuxTiSe2
Marcello Spera, Alessandro Scarfato, Enrico Giannini and Christoph Renner
Physical Review. B, Condensed Matter 99 155133, 1-7 (2019)
We report a detailed study of the microscopic effects of Cu intercalation on the charge density wave (CDW) in 1T-CuxTiSe2. Scanning tunneling microscopy and spectroscopy reveal a unique, Cu-driven spatial texturing of the charge-ordered phase, with the appearance of energy-dependent CDW patches and …
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A spin–orbit playground: surfaces and interfaces of transition metal oxides
Stefano Gariglio, Andrea Caviglia, Jean-Marc Triscone and M Gabay
Reports on Progress in Physics 82 012501 (2019)
Within the last twenty years, the status of the spin–orbit interaction has evolved from that of a simple atomic contribution to a key effect that modifies the electronic band structure of materials. It is regarded as one of the basic ingredients for spintronics, locking together charge and spin…
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Towards surface diffusion potential mapping on atomic length scale
Renan Villarreal, Christopher J. Kirkham, Alessandro Scarfato, David R. Bowler and Christoph Renner
Journal of Applied Physics 125 18, 184301 (2019)
The surface diffusion potential landscape plays an essential role in a number of physical and chemical processes such as self-assembly and catalysis. Diffusion energy barriers can be calculated theoretically for simple systems, but there is currently no experimental technique to systematically…
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Strain-engineering Mott-insulating La2CuO4
O. Ivashko, M. Horio, W. Wan, N. B. Christensen, D. E. McNally, E. Paris, Y. Tseng, N. E. Shaik, H. M. Rønnow, H. I. Wei, C. Adamo, Céline Lichtensteiger, M. Gibert, M. R. Beasley, K. M. Shen, J. M. Tomczak, T. Schmitt and J. Chang
Nature Communications 10 1, 1-8 (2019)
The transition temperature Tc of unconventional superconductivity is often tunable. For a monolayer of FeSe, for example, the sweet spot is uniquely bound to titanium-oxide sub- strates. By contrast for La2−xSrxCuO4 thin films, such substrates are sub-optimal and the highest Tc is instead…
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Structural, elastic and vibrational properties of celestite, SrSO4, from synchrotron x-ray diffraction, thermal diffuse scattering and Raman scattering
Adrien Girard, Michal Stekiel, Dominik Spahr, Wolfgang Morgenroth, Björn Wehinger, Victor Milman, Tra Nguyen-Thanh, Alessandro Mirone, Arianna Minelli, Luigi Paolasini, Alexei Bosak and Bjoern Winkler
Journal of Physics. Condensed Matter 31 5, 055703 (2019)
In order to resolve inconsistencies encountered in published data for SrSO, the elasticity and the phase stability of celestite has been studied using thermal diffuse scattering, high pressure powder synchrotron x-ray diffraction, Raman scattering and DFT calculations. The structure of SrSO is…
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Solving and refining inorganic structures
Radovan Cerny and Vincent Favre-Nicolin
International Tables for Crystallography. Volume H, Powder Diffraction, Chapter4.5,p.442-451 (2019)
Powder diffraction is the mostly widely used crystallographic method, with applications spanning all aspects of structural science. This new volume of International Tables for Crystallography covers all aspects of the technique with over 50 chapters written by experts in the field. Consisting of…
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Phase Stability and Fast Ion Conductivity in the Hexagonal LiBH4–LiBr–LiCl Solid Solution
Valerio Gulino, Matteo Brighi, Erika M. Dematteis, Fabrizio Murgia, Radovan Nervi, Radovan Cerny and Marcello Baricco
Chemistry of Materials 31 14, 5133-5144 (2019)
This study shows a flexible system that offers promising candidates for Li-based solid-state electrolytes. The Br− substitution for BH4 − stabilizes the hexagonal structure of LiBH4 at room temperature (RT), whereas Cl− is soluble only at higher temperatures. Incorporation of chloride in a…
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Improvement of the ionic conductivity on new substituted borohydride argyrodites
Anh Ha Dao, Radovan López-Aranguren, Radovan Cerny, Olivier Guiader, Junxian Zhang, Fermín Cuevas, Michel Latroche and Christian Jordy
Solid State Ionics 339 114987, 1-6 (2019)
The development of electrochemically stable Li-ion solid electrolytes with high conductivity is crucial for a successful performance of all-solid-state batteries. Li-containing argyrodite sulfides with the formula Li6PS5Z (Z=Cl, Br, I) are considered as promising solid electrolytes due to their…
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Holographic imaging of the complex charge density wave order parameter
Arpad Pasztor, Alessandro Scarfato, Marcello Spera, Céline Barreteau, Enrico Giannini and Christoph Renner
Physical Review Research 1 3, 033114 (2019)
The charge density wave (CDW) in solids is a collective ground state combining lattice distortions and charge ordering. It is defined by a complex order parameter with an amplitude and a phase. The amplitude and wavelength of the charge modulation are readily accessible to experiment. However,…
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Nanoscale investigations of the LaAlO3/SrTiO3 interface
Margherita Boselli
Thèse (2019)
In 2004 Ohtomo and Hwang discovered that the interface between two band insulators, LaAlO3 and SrTiO3, is conducting. This thesis focuses on the properties of the LaAlO3/SrTiO3 interface at the nanoscale. First, we developed a technique to realize conducting wires of nanometric scale in insulating…
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Vers une excellence démocratique
Stéphanie Girardclos, Mathilde Fontanet, Yasmine Atlas, Sébastien Muller, Mathieu Crettenand, Didier Maurice Grandjean, Léonard Truscello, Romain Alexandre Boillat, Ignace Cuttat and Olivier Maulini
Rapport de recherche, 28 (2019)
Rapport de la Commission de l’Assemblée de l’Université de Genève chargée de recenser les problèmes de gouvernance institutionnels et leurs conséquences pour les membres de la communauté afin de formuler des suggestions.
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Interacting bosons in generalized zigzag and railroad-trestle models
Sebastian Greschner and Tapan Mishra
Physical Review. B, Condensed Matter 100 14, 144405 (2019)
We theoretically study the ground-state phase diagram of strongly interacting bosons on a generalized zigzag ladder model, the railroad-trestle (RRT) model. By means of analytical arguments in the limits of decoupled chains and the case of vanishing fillings as well as extensive DMRG calculations,…
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Tomonaga-Luttinger Liquid Spin Dynamics in the Quasi-One-Dimensional Ising-Like Antiferromagnet BaCo2V2O8
Quentin Faure, Shintaro Takayoshi, Virginie Simonet, Béatrice Grenier, Martin Månsson, Jonathan S. White, Gregory S. Tucker, Christian Ruegg, Pascal Lejay, Thierry Giamarchi and Sylvain Petit
Physical Review Letters 123 2, 027204 (2019)
Combining inelastic neutron scattering and numerical simulations, we study the quasi-one-dimensional Ising anisotropic quantum antiferromagnet BaCo2V2O8 in a longitudinal magnetic field. This material shows a quantum phase transition from a Ne ́el ordered phase at zero field to a longitudinal…
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Vanishing Hall Response of Charged Fermions in a Transverse Magnetic Field
Michele Filippone, Charles Bardyn, Sebastian Greschner and Thierry Giamarchi
Physical Review Letters 123 8, 086803 (2019)
We study the Hall response of two-dimensional lattice systems of charged fermions in a transverse magnetic field, in the ballistic coherent limit. We identify a setup in which this response vanishes over wide regions of parameter space: the “Landauer-Büttiker” setup commonly studied for…
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Polarization dependence of angle-resolved photoemission with submicron spatial resolution reveals emerging one-dimensionality of electrons in NbSe3
M. A. Valbuena, P. Chudzinski, S. Pons, S. Conejeros, P. Alemany, E. Canadell, H. Berger, E. Frantzeskakis, J. Avila, M. C. Asensio, Thierry Giamarchi and M. Grioni
Physical Review. B, Condensed Matter 99 7, 075118 (2019)
In materials with nearly commensurate band filling the electron liquid may spontaneously separate into components with distinct properties, yielding complex intra- and interunit cell ordering patterns and a reduced dimensionality. Polarization-dependent angle-resolved photoemission data with…
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High-harmonic generation in quantum spin systems
Shintaro Takayoshi, Yuta Murakami and Philipp Werner
Physical Review. B, Condensed Matter 99 18, 184303 (2019)
We theoretically study the high-harmonic generation (HHG) in one-dimensional spin systems. While in electronic systems the driving by ac electric fields produces radiation from the dynamics of excited charges, we consider here the situation where spin systems excited by a magnetic field pulse…
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Dynamics of a mobile impurity in a two-leg bosonic ladder
Naushad Ahmad Kamar, Adrian Kantian and Thierry Giamarchi
Physical Review. A 100 2, 023614 (2019)
We analyze the behavior of a mobile quantum impurity, restricted to a one-dimensional motion, in a bath formed by a two-leg bosonic ladder through a combination of field theory [Tomonaga-Luttinger liquid (TLL)] and numerical (density-matrix renormalization group) techniques. We compute the Green’s…
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Bulk pumping in two-dimensional topological phases
Charles Bardyn, Michele Filippone and Thierry Giamarchi
Physical Review. B, Condensed Matter 99 3, 035150 (2019)
The notion of topological (Thouless) pumping in topological phases is traditionally associated with Laughlin’s pump argument for the quantization of the Hall conductance in two-dimensional (2D) quantum Hall systems. It relies on magnetic flux variations that thread the system of interest without…
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Momentum-resolved lattice dynamics of parent and electron-doped Sr2IrO4
C.D. Dashwood, H. Miao, J.G. Vale, D. Ishikawa, D.A. Prishchenko, V.V. Mazurenko, V.G. Mazurenko, R.S. Perry, G. Cao, Alberto De La Torre, Felix Baumberger, A.Q.R. Baron, D.F. McMorrow and M.P.M. Dean
Physical Review. B, Condensed Matter 100 085131, 1-8 (2019)
The mixing of orbital and spin character in the wave functions of the 5d iridates has led to predictions of strong couplings among their lattice, electronic, and magnetic degrees of freedom. As well as realizing a novel spin-orbit assisted Mott-insulating ground state, the perovskite iridate…
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Mapping spin–charge conversion to the band structure in a topological oxide two-dimensional electron gas
Diogo C. Vaz, Paul Noël, Annika Johansson, Börge Göbel, Flavio Yair Bruno, Gyanendra Singh, Siobhan Mckeown Walker, Felix Trier, Luis M. Vicente-Arche, Anke Sander, Sergio Valencia, Pierre Bruneel, Manali Vivek, Marc Gabay, Nicolas Bergeal, Felix Baumberger, Hanako Okuno, Agnès Barthélémy, Albert Fert, Laurent Vila, Ingrid Mertig, Jean-Philippe Attané and Manuel Bibes
Nature Materials (2019)
While spintronics has traditionally relied on ferromagnetic metals as spin generators and detectors, spin–orbitronics exploits the efficient spin–charge interconversion enabled by spin–orbit coupling in non-magnetic systems. Although the Rashba pic- ture of split parabolic bands is often used …
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Probing magnetism in 2D materials at the nanoscale with single-spin microscopy
L. Thiel, Zhe Wang, M. A. Tschudin, D. Rohner, Ignacio Gutierrez Lezama, Nicolas Ubrig, Marco Gibertini, Enrico Giannini, Alberto Morpurgo and P. Maletinsky
Science 364 6444, 973-976 (2019)
The discovery of ferromagnetism in two-dimensional (2D) van der Waals (vdW) crystals has generated widespread interest. Making further progress in this area requires quantitative knowledge of the magnetic properties of vdW magnets at the nanoscale. We used scanning single-spin magnetometry based on …
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Low-dimensional correlations under thermal fluctuations
Noam Kestin and Thierry Giamarchi
Physical Review. B, Condensed Matter 99 195121 (2019)
We study the correlation functions of quantum spin 1/2 ladders at finite temperature, under a magnetic field, in the gapless phase at various relevant temperatures T≠0, momentum q and frequencies ω. We compute those quantities using the time dependent density matrix renormalization group…
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High-Resolution Photoemission on Sr2RuO4 Reveals Correlation-Enhanced Effective Spin-Orbit Coupling and Dominantly Local Self-Energies
Anna Tamai, M. Zingl, E. Rozbicki, Edoardo Cappelli, Sara Ricco, Alberto De La Torre, Siobhan Mckeown Walker, Flavio Yair Bruno, P.D.C. King, W. Meevasana, M. Shi, M. Radovic, N.C. Plumb, A.S. Gibbs, A.P. Mackenzie, Christophe Berthod, Hugo Strand, M. Kim, Antoine Georges and Felix Baumberger
Physical Review X 9 021048, 1-18 (2019)
We explore the interplay of electron-electron correlations and spin-orbit coupling in the model Fermi liquid Sr2RuO4 using laser-based angle-resolved photoemission spectroscopy. Our precise measurement of the Fermi surface confirms the importance of spin-orbit coupling in this material and reveals…
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Thickness-Dependent Perovskite Octahedral Distortions at Heterointerfaces
Jennifer Fowlie, Céline Lichtensteiger, Marta Gibert Gutierrez, Hugo Meley, Philip Willmott and Jean-Marc Triscone
Nano Letters 19 6, 4188-4194 (2019)
In this study, we analyze how the octahedral tilts and rotations of thin films of LaNiO₃ and LaAlO₃ grown on different substrates, determined using synchrotron X-ray diffraction-measured half-integer Bragg peaks, depend upon the total film thickness. We find a striking difference between films…
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3-D Thermal-Electric Finite Element Model of a Nb3Sn Coil During a Quench
José Ferradas Troitino, Giorgio Ambrosio, Hugo Bajas, Bernardo Bordini, Paolo Ferracin, Jerome Fleiter, Susana Izquierdo Bermudez, Jose Vicente Lorenzo Gomez, Juan Carlos Perez, Giorgio Vallone and Carmine Senatore
IEEE Transactions on Applied Superconductivity 29 5, 1-6 (2019)
High field superconducting magnets for particle accelerators often exhibit premature quenches. Once a normal zone is generated within the conductor, the quench may propagate causing temperature and resistive voltage rise along the coil. The resulting thermal gradients can potentially cause new peak …
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High sensitivity variable-temperature infrared nanoscopy of conducting oxide interfaces
Weiwei Luo, Margherita Boselli, Jean-Marie Poumirol, Ivan Ardizzone, Jérémie Teyssier, Dirk Van Der Marel, Stefano Gariglio, Jean-Marc Triscone and Alexey Kuzmenko
Nature Communications 10 2774 (2019)
Probing the local transport properties of two-dimensional electron systems (2DES) confined at buried interfaces requires a non-invasive technique with a high spatial resolution operating in a broad temperature range. In this paper, we investigate the scattering-type scanning near field optical…
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Enhanced Electron-Phonon Interaction in Multivalley Materials
Thibault Sohier, Evgeniy Ponomarev, Marco Gibertini, Helmuth Berger, Nicola Marzari, Nicolas Ubrig and Alberto Morpurgo
Physical Review X 9 3, 031019 (2019)
We report a combined experimental and theoretical investigation that reveals a new mechanism responsible for the enhancement of electron-phonon coupling in doped semiconductors in which multiple inequivalent valleys are simultaneously populated. Using Raman spectroscopy on ionic-liquid-gated…
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Steady states of interacting Floquet insulators
Karthik I. Seetharam, Charles Bardyn, Netanel H. Lindner, Mark S. Rudner and Gil Refael
Physical Review. B, Condensed Matter 99 1, 014307 (2019)
Floquet engineering offers tantalizing opportunities for controlling the dynamics of quantum many-body systems and realizing new nonequilibrium phases of matter. However, this approach faces a major challenge: generic interacting Floquet systems absorb energy from the drive, leading to uncontrolled …
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Laser control of magnonic topological phases in antiferromagnets
Kouki Nakata, Se Kwon Kim and Shintaro Takayoshi
Physical Review. B, Condensed Matter 100 1, 014421 (2019)
We study the laser control of magnon topological phases induced by the Aharonov-Casher effect in insulating antiferromagnets (AFs). Since the laser electric field can be considered as a time-periodic perturbation, we apply the Floquet theory and perform the inverse frequency expansion by focusing…
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Three-body constrained bosons in a double-well optical lattice
Suman Mondal, Sebastian Greschner and Tapan Mishra
Physical Review. A 100 1, 013627 (2019)
We analyze the ground-state properties of three-body constrained bosons in a one-dimensional optical lattice with staggered hoppings analogous to the double-well optical lattice. By considering attractive and repulsive on-site interactions between the bosons, we obtain the phase diagram which…
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Universal Hall Response in Interacting Quantum Systems
Sebastian Greschner, Michele Filippone and Thierry Giamarchi
Physical Review Letters 122 8, 083402 (2019)
We theoretically study the Hall effect on interacting M-leg ladder systems, comparing different measures and properties of the zero temperature Hall response in the limit of weak magnetic fields. Focusing on SU(M) symmetric interacting bosons and fermions, as relevant for, e.g., typical synthetic…
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Possible mechanism for superconductivity in doped SrTiO3
Dirk Van Der Marel, Francesco Barantani and Willem Rischau
Physical Review Research 1 013003 (2019)
The soft ferroelectric phonon in SrTiO3observed with optical spectroscopy has an extraordinarily strongspectral weight which is much stronger than expected in the limit of a perfectly ionic compound. This “chargedphonon” effect in SrTiO3is caused by the close-to-covalent character of the Ti-O…
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Ultrafast Spin Dynamics in Photodoped Spin-Orbit Mott Insulator Sr2IrO4
D. Afanasiev, A. Gatilova, D. J. Groenendijk, B. A. Ivanov, Marta Gibert Gutierrez, Stefano Gariglio, J. Mentink, J. Li, N. Dasari, M. Eckstein, Th. Rasing, Andrea Caviglia and A. V. Kimel
Physical Review X 9 021020 (2019)
Ultrafast photodoping of the Mott insulators, possessing strong correlation between electronic and magnetic degrees of freedom, holds promise for launching an ultrafast dynamics of spins which cannot be described in terms of conventional models of ultrafast magnetism. Here we study the ultrafast…
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Reduced strain sensitivity of the critical current of Nb3Sn multifilamentary wires
Bernd Seeber, Ciro Calzolaio, Damien Zurmuehle, Vital Christof Abacherli, M. Alessandrini, G. De Marzi and Carmine Senatore
Journal of Applied Physics 126 203905 (2019)
Strain plays an important role in Nb3Sn multifilamentary wires because critical current depends on it and strain sensitivity of Ic increases at higher magnetic fields. In this paper, a three-dimensional strain data set becomes available by further analysis of an earlier study of the Nb3Sn lattice…
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The 16 T Dipole Development Program for FCC and HE-LHC
Daniel Schoerling, Diego Arbelaez, Bernhard Auchmann, Marta Bajko, Amalia Ballarino, Emanuela Barzi, Giovanni Bellomo, Michael Benedikt, Susana Izquierdo Bermudez, Bernardo Bordini, Luca Bottura, Lucas Brouwer, Pierluigi Bruzzone, Barbara Caiffi, Shlomo Caspi, Ananda Chakraborti, Eric Coatanea, Gijs DeRijk, Marc Dhalle, Maria Durante, Pasquale Fabbricatore, Stefania Farinon, Helene Felice, Alejandro Fernandez, Inigo Sancho Fernandez, Peng Gao, Barbara Gold, Thodoris Gortsas, Steve Gourlay, Mariusz Juchno, Vadim Kashikhin, Charilaos Kokkinos, Sotiris Kokkinos, Kari Koskinen, Friedrich Lackner, Clement Lorin, Konstantinos Loukas, Alexandre Louzguiti, Kari Lyytikainen, Samuele Mariotto, Maxim Marchevsky, Giuseppe Montenero, Javier Munilla, Igor Novitski, Toru Ogitsu and Carmine Senatore
IEEE Transactions on Applied Superconductivity 29 4003109 (2019)
A future circular collider (FCC) with a center-of-mass energy of 100 TeV and a circumference of around 100 km, or an energy upgrade of the LHC (HE-LHC) to 27 TeV require bending magnets providing 16 T in a 50-mm aperture. Several development programs for these magnets, based on Nb 3 Sn technology,…
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AMS-100: The next generation magnetic spectrometer in space – An international science platform for physics and astrophysics at Lagrange point 2
S. Schael, A. Atanasyan, J. Berdugo, T. Bretz, M. Czupalla, B. Dachwald, P. von Doetinchem, M. Duranti, H. Gast, W. Karpinski, T. Kirn, K. Lübelsmeyer, C. Maña, P.S. Marrocchesi, P. Mertsch, I.V. Moskalenko, T. Schervan, M. Schluse, K.-U. Schröder, A. Schultz von Dratzig, Carmine Senatore, L. Spies, S.P. Wakely, M. Wlochal, Davide Uglietti and J. Zimmermann
Nuclear Instruments and Methods in Physics Research. A 944 162561 (2019)
The next generation magnetic spectrometer in space, AMS-100, is designed to have a geometrical acceptance of 100 m 2 sr and to be operated for at least ten years at the Sun–Earth Lagrange Point 2. Compared to existing experiments, it will improve the sensitivity for the observation of new…
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Band Structure and Spin–Orbital Texture of the (111)‐KTaO3 2D Electron Gas
Flavio Yair Bruno, Siobhan Mckeown Walker, Sara Ricco, Alberto De La Torre, Zhiming Wang, Anna Tamai, Timur K. Kim, Moritz Hoesch, Mohammad S. Bahramy and Felix Baumberger
Advanced Electronic Materials 5 1800860, 1-7 (2019)
2D electron gases (2DEGs) in oxides show great potential for the discovery of new physical phenomena and at the same time hold promise for electronic applications. In this work, angle-resolved photoemission is used to determine the electronic structure of a 2DEG stabilized in the (111)-oriented…
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Robust cerebrovascular blood velocity and flow rate estimation from 4D CTA
Pierre Bouillot, Olivier Brina, Christophe Chnafa, Nicole M Cancelliere, Maria Isabel Vargas Gomez, Ivan Radovanovic, Timo Krings, David A Steinman and Vitor M Pereira
Medical Physics 46 5, 2126-2136 (2019)
Blood velocity and flow rate information may be helpful for a wide variety of applications, but it often requires separate acquisitions. The dynamic information combined with the high spatial resolution of 4D-CTA offers the possibility to quantify blood flow simultaneous to vascular anatomy.
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Hydrated and anhydrous dodecahydro closo-dodecaborates of 3d transition metals and of magnesium
Emilie Yvonne Jeanne Didelot, Yolanda Sadikin, Zbigniew Łodziana and Radovan Cerny
Solid State Sciences 90, 86-94 (2019)
Magnesium and 3d transition metals closo-dodecaborates were prepared by mechanosynthesis (ball milling) of the mixtures Na2B12H12 + MCl2 (M=Ti, Cr, Mn, Fe, Co, Cu, Zn, Mg) and CuCl, followed by hydration and drying under dynamic vacuum. The crystal structures of hydrated and anhydrous…
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