Divergence of dielectric permittivity near phase transition within ferroelectric domain boundaries

Abstract

Phase-field simulations based on Ginzburg–Landau–Devonshire model were utilised to demonstrate and quantify the enhancement of the dielectric permittivity of multidomain rhombohedral BaTiO₃ crystal in the vicinity of the Bloch-type to Ising-type phase transition within 180° domain boundaries with crystallographic orientation. The phase transition is driven by compressive mechanical stress applied in the plane perpendicular to the spontaneous polarisation direction. Simulations reveal a classical Curie–Weiss behaviour of the transverse component of dielectric permittivity, expected in the vicinity of a second-order phase transition.

Keywords:

• Bloch wall
• domain boundary
• BaTiO₃
• Ginzburg–Landau–Devonshire theory
• permittivity

Acknowledgements

This work was supported by Project GACR P204/10/0616 of the Czech Science Foundation.