Nonequilibrium dynamical mean field simulation of inhomogeneous systems

TL;DR

This paper develops a nonequilibrium dynamical mean field approach for inhomogeneous systems, enabling the study of complex layered materials under various excitations and biases.

Contribution

It extends the real-space DMFT formalism to inhomogeneous systems using Keldysh Green's functions and applies it to layered Mott insulators with strong local interactions.

Findings

Studied diffusion of photo-created doublons and holes.

Analyzed time-dependent polarization and current in layered structures.

Explored photo-induced current in Mott insulators under bias.

Abstract

We extend the nonequilibrium dynamical mean field (DMFT) formalism to inhomogeneous systems by adapting the "real-space" DMFT method to Keldysh Green's functions. Solving the coupled impurity problems using strong-coupling perturbation theory, we apply the formalism to homogeneous and inhomogeneous layered systems with strong local interactions and up to 39 layers. We study the diffusion of doublons and holes created by photo-excitation in a Mott insulating system, the time-dependent build-up of the polarization and the current induced by a linear voltage bias across a multi-layer structure, and the photo-induced current in a Mott insulator under bias.