Day / Time
Date(s) - 02/12/2014
13 h 00 min - 14 h 00 min
Ecole de Physique, Auditoire Stueckelberg, 24 quai Ernest-Ansermet
Charge order in cuprate superconductors
Laboratoire National des Champs Magnétiques Intenses, Grenoble
Whether high-Tc cuprates are generically prone to charge-density-wave (CDW) formation and whether this has any importance for understanding their superconductivity has been debated for more than twenty years. After recalling earlier evidence of two specific cases of charge order, I will illustrate how the discovery of charge order in ultra-clean YBa2Cu3Oy has given a new twist to the field with charge order being now observed in virtually all cuprate families.
Specifically, I will describe how the direct NMR evidence that superconductivity coexists, but competes, with CDW order in high magnetic fields led us to argue that cuprates are generically unstable towards CDW formation . Then, I will discuss how this discovery relates to the flurry of subsequent works, especially the X-ray scattering  and NMR  evidence of short-range CDW order in the normal state of YBa2Cu3Oy. The relationship with various electronic anomalies in the pseudogap regime (including other, putative, electronic orders) will also be discussed together with the role of disorder in shaping part of this phenomenology.
 T. Wu et al. Nature 477, 191 (2011). Nature Commun. 4, 2113 (2013).
 G. Ghiringhelli et al. Science 337, 821 (2012). A.J. Achkar et al. Phys. Rev. Lett. 109, 167001 (2012). J. Chang et al. Nature Phys. 8, 871 (2012).
 T. Wu et al. Incipient charge order observed by NMR in the normal state of YBa2Cu3Oy. Preprint (2014).
Work performed with T. Wu, M. Hirata, H. Mayaffre, S. Krämer, M. Horvatić, C. Berthier (LNCMI Grenoble), P.L. Kuhns & A.P. Reyes (NHMFL, Tallahassee, USA), W.N. Hardy, R. Liang & D. A. Bonn (University of British Columbia, Vancouver, Canada) and funded by Université J. Fourier – Grenoble and by the French Agence Nationale de la Recherche (ANR) under reference AF-12-BS04-0012-01 (Superfield).