Crystal-Liquid phase transition of polarization curl density in PbTiO$_3$/SrTiO$_3$ superlattices

ORAL

Abstract

Recent studies of the temperature evolution of the polarization patterns in oxide superlattices shows complex behaviour [1-3] different from the classical ferro/paraelectric phase transitions where the polarization is the relevant order parameter to track.

Using second-principles methods as implemented in the Scale-UP [4] code we report a first-order crystal-liquid like temperature-driven phase transition in (PbTiO$_3$)$_n$/(SrTiO$_3$)$_n$ superlattices in which the relevant order parameter is related with the curl density of the polarization pattern. Different values of the perioditiy $n=8,~10,~14$ were studied showing good scaling for the phase transition. 

[1] Y. Nahas, et al., Phys. Rev. Lett. 119, 117601 (2017)

[2] C. Xu, et al., Phys. Rev. B. 101, 241402 (2020)

[3] Y. Nahas, et al., Nature 577, 47–51 (2020)

[4] P. Garc\'ia-Fern\'andez, et al., Phys. Rev. B 93 195137 (2016)

*J. J., P.G.F., F.G.O Grant No. PGC2018-096955-B-C41, Spanish Ministery of Science, Innovation. F.G.O Grant No. FPU18/04661, Spanish Ministery of Universities. J.M.L Grant No.FIS2016-74957-P State Investigation Agency (Spain) and FEDER (EU).

Presenters

  • Fernando Gómez-Ortiz

    • CITIMAC, Universidad de Cantabria, Avenida de los Castros s/n

Authors

  • Fernando Gómez-Ortiz

    • CITIMAC, Universidad de Cantabria, Avenida de los Castros s/n
  • Juan M. López

    • Instituto de Física de Cantabria, CSIC–Universidad de Cantabria, Avenida de Los Castros s/n, E-39005 Santander, Spain
  • Pablo García-Fernández

    • Universidad de Cantabria
    • CITIMAC, Universidad de Cantabria, Avenida de los Castros s/n
  • Javier Junquera

    • Univ de Cantabria
    • CITIMAC, Universidad de Cantabria, Avenida de los Castros s/n