Theoretical description of pump/probe experiments in electron mediated charge-density-wave insulators

TL;DR

This paper develops a theoretical framework for understanding pump/probe experiments in charge-density-wave insulators, combining exact solutions in simple models with nonequilibrium dynamical mean-field theory for more complex systems.

Contribution

It introduces a formalism for describing ultrafast pump/probe experiments in charge-density-wave insulators, including exact results and numerical solutions for the Falicov-Kimball model.

Findings

Formalism for charge-density-wave insulators in pump/probe experiments

Exact solutions for simple noninteracting models

Numerical results using nonequilibrium dynamical mean-field theory

Abstract

In this review, we develop the formalism employed to describe charge-density-wave insulators in pump/probe experiments using ultra short driving pulses of light. The theory emphasizes exact results in the simplest model for a charge-density wave insulator (given by a noninteracting systems with two bands and a gap) and by employing nonequilibrium dynamical mean-field theory to solve the Falicov-Kimball model in its ordered phase. We show both how to develop the formalism and how the solutions behave. Care is taken to describe the details behind these calculations and to show how to verify their accuracy via sum-rule constraints.