Day / Time
Date(s) - 12/04/2016
13 h 00 min - 14 h 30 min
Mardi 15 mars 2016 à 13.00
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.
Illustration: An Ising line defect in rhombohedral BaTiO3
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