First-principles approach to insulators in finite electric fields.
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.
Souza
Ivo
I
Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
Iñiguez
Jorge
J
Vanderbilt
David
D