Title: Teaching an old dog new tricks: switchable polar materials from first principles
Abstract: First-principles methods have proved over recent years to be an increasingly powerful tool for the design and discovery of new materials with switchable functional behavior driven by applied electric fields and stress, typified by ferroelectrics, which have two or more symmetry-equivalent polarization states that can be switched by an applied electric field. This talk will go beyond textbook ferroelectrics to discuss:
1) identification of new functional materials characterized by
symmetry-inequivalent competing low-energy states, including antiferroelectrics, double ferroelectrics, and “fraternal-twin” ferroelectrics, and
(2) investigation of the rich physics of ferroelectrics with added electrons, including leaky ferroelectrics, deliberately doped ferroelectrics, charge-order- driven ferroelectrics, and polar metals and semi-metals. While the focus will be on simulations and modeling in “first principles world,” contact with experiment will be made for specific systems and the development of “virtual instrument” tools that connect first-principles results to experimental measurements.