A First-Principles Approach to Insulators in Finite Electric Fields

TL;DR

This paper introduces a first-principles computational method to analyze insulators' responses to static electric fields, identifying breakdown points and calculating dielectric properties.

Contribution

It presents a novel iterative minimization technique of an electric enthalpy functional for insulators under finite electric fields, including breakdown prediction.

Findings

Method successfully computes dielectric susceptibilities of III-V semiconductors.

Identifies critical electric field E_c where insulator response minima vanish.

Demonstrates applicability to piezoelectric and nonlinear dielectric properties.

Abstract

We describe a method for computing the response of an insulator to a static, homogeneous electric field. It consists of iteratively minimizing an electric enthalpy functional expressed in terms of occupied Bloch-like states on a uniform grid of k points. The functional has equivalent local minima below a critical field E_c that depends inversely on the density of k points; the disappearance of the minima at E_c signals the onset of Zener breakdown. We illustrate the procedure by computing the piezoelectric and nonlinear dielectric susceptibility tensors of III-V semiconductors.