Discretized Diagonalization for Efficient Berry Curvature Integration: Application to Electric Polarization
ORAL
Abstract
An important property in characterizing the response of a material to an electric field is the induced change in electric polarization. For periodic systems, the modern theory of polarization relates this change to a change in the Berry phase, raising the question of the correct choice of branch. In this talk, I present a new method for predicting the electric-field-induced change in polarization using only the wavefunctions of only the initial and final states, based on finely subdividing the relevant phase change into gauge-invariant pieces. The underlying assumptions are automatically checked within the method and are valid for most known ferroelectrics, allowing the computation of switching polarization without the need to identify an explicit path or to perform calculations for intermediate states. The extension of this approach to the computation of other quantities expressed in terms of Berry curvature, notably topological invariants, will be discussed.
–
Presenters
-
John Bonini
- Rutgers University, New Brunswick