Melting of Polarization Vortices Crystals and Chiral Phase Transitions in Oxide Superlattices

Abstract

We study the equilibrium arrangements of polarization vortices in (PbTiO${}_3$)${}_n$/(SrTiO${}_3$)${}_n$ superlattices by means of second-principles simulations. We find that, at low temperatures, polarization vortices organize in a regular arrangement in which clockwise and counter-clockwise vortices alternate positions, leading to a crystal-like structure with well defined handedness. This chiral crystal melts at a critical temperature $T_{\mathrm{M}}$ into a chiral liquid, where long-range order is lost but handedness is preserved. At even higher temperatures, $T_{\mathrm{C}}$, a second phase transition occurs, at which the chiral liquid of polarization vortices loses its handedness. Both phase transitions can be readily identified by the adequate choices of order parameters.

arXiv comment7 pages, 4 figures

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Cited by in corpus (4)

• Assessing the nature of nanoscale ferroelectric domain walls in lead titanate multilayers
• Topological phase transitions in perovskite superlattices driven by temperature, electric field, and doping
• Kittel law and domain formation mechanism in PbTiO${}_3$/SrTiO${}_3$ superlattices
• Liquid-crystal-like dynamic transition in ferroelectric/dielectric superlattices