DQMP Seminar by Professor Jiri Hlinka

Carte non disponible

Day / Time
Date(s) - 12/04/2016
13 h 00 min - 14 h 30 min

Category


Mardi 15 mars 2016 à 13.00
Auditoire Stückelberg
Ecole de physique

Ferroelectric Bloch domain walls and walls within walls

Ferromagnetic and ferroelectric domain walls are often quoted as examples of topological defects and a great attention has been paid to the correspondence between various possible linear and planar defects of the polarization field in ferroelectrics and of the magnetization field in ferromagnets. Such comparisons could sometimes disclose overlooked possibilities or drive new understanding.  For example, there have been many reports about various extended defects in perovskite ferroelectrics, suggesting manifestation of the local “polarization rotation”.  It can be argued that this is a signature of  reduced crystalline anisotropy and soft enough short-range interactions. In fact, in this case the analogies between magnetic and ferroelectric defects are more pronounced.

In our group, we have been studying a range of specific ferroelectric domain walls or their junctions within the framework of Ginzburg-Landau-Devonshire theory and phase-field simulations, mostly using a model tuned to ferroelectric BaTiO3. In this contribution, I would like to review the results and prospects of these research activities from the above sketched point of view.

Ising line defect

Illustration: An Ising line defect in rhombohedral BaTiO3

 

 

References:

1.P. Marton, I. Rychetsky and J. Hlinka, Phys. Rev. B 81, 144125 (2010).
2.J. Hlinka, V. Stepkova, P. Marton, I. Rychetsky, V. Janovec and P. Ondrejkovic, Phase Transitions 84 , 738 (2011).
3.V. Stepkova, P. Marton and J. Hlinka, J. Phys: Condens. Matter 24, 212201 (2012).
4.M. Taherinejad, D. Vanderbilt, P. Marton, V. Stepkova and J. Hlinka, Phys. Rev. B 86, 155138 (2012).
5.V. Stepkova, P. Marton and J. Hlinka, Phys. Rev. B 92, 094106 (2015).

 

Réalisation : Sur Mesure concept