Computational Studies of Lead-based Relaxor Ferroelectrics

Abstract

Relaxor ferroelectrics have been a focus of intense attention due to their fascinating physical properties. Their diffuse phase transitions have been explained by the polar nanoregion model. Nevertheless, fundamental characterization of structure and dynamics in relaxors is still a long-standing challenge. Better scientific understanding of the microscopic origins of relaxor behavior is also required to improve efficiencies of relaxor based devices. Our molecular dynamics studies in 0.75PbMg_1/3Nb_2/3O₃-0.25PbTiO₃ showed good agreement with experimental data and revealed conflicts with the current polar nanoregion model. Here, we review our work and propose an alternate model for structure and dynamics in the relaxor phase.

Keywords:

• Relaxor ferroelectrics
• dielectric dispersion
• dipole relaxation time
• dynamics

Additional information

Funding

This work was supported by the Office of Naval Research, under Grant No. N00014-12-1-1033 and by the NSF under grant DMR-1124696. Computational support was provided by a Challenge Grant from the HPCMO of the U.S. Department of Defense.