ScholarlyCommons

Title

Anisotropic Local Correlations and Dynamics in a Relaxor Ferroelectric

Author(s)

Hiroyuki Takenaka, University of Pennsylvania
Ilya Grinberg, University of Pennsylvania
Andrew M. Rappe, University of PennsylvaniaFollow

Document Type

Journal Article

Date of this Version

4-5-2013

Abstract

Relaxor ferroelectrics have been a focus of intense attention due to their anomalous properties, and understanding the structure and dynamics of relaxors has been one of the long-standing challenges in solid-state physics. We investigate the local structure and dynamics in 75%PbMg_1/3Nb_2/3O₃-25%PbTiO₃ using molecular dynamics simulations and the dynamic pair distribution function technique. We show that relaxor transitions can be described by local order parameters. The relaxor phase is characterized by the presence of highly anisotropic correlations between the local cation displacements that resemble the hydrogen bond network in water. This contradicts the current model of polar nanoregion inside a nonpolar matrix. We therefore suggest a new model of a homogeneous random network of anisotropically coupled dipoles.

Comments

Takenaka, H., Grinberg, I., & Rappe, A. M. (2013). Anisotropic Local Correlations and Dynamics in a Relaxor Ferroelectric. Physical Review Letters, 110(14), 147602. doi: 10.1103/PhysRevLett.110.147602

© 2013 American Physical Society

Recommended Citation

Takenaka, H., Grinberg, I., & Rappe, A. M. (2013). Anisotropic Local Correlations and Dynamics in a Relaxor Ferroelectric. Retrieved from https://repository.upenn.edu/physics_papers/277