Theory of time-resolved optical spectroscopy on correlated electron systems

TL;DR

This paper develops a theoretical framework using dynamical mean-field theory to analyze time-resolved optical spectroscopy data, specifically relating reflectivity to nonequilibrium optical conductivity in correlated electron systems.

Contribution

It introduces a method to express nonequilibrium optical conductivity in terms of real-time Green functions within dynamical mean-field theory.

Findings

Demonstrates the approach on the Falicov-Kimball model

Analyzes ultrafast formation of the gapped phase

Provides insights into electron dynamics in correlated materials

Abstract

The real-time dynamics of interacting electrons out of equilibrium contains detailed microscopic information about electronically correlated materials, which can be read out with time-resolved optical spectroscopy. The reflectivity that is typically measured in pump-probe experiments is related to the nonequilibrium optical conductivity. We show how to express this quantity in terms of real-time Green functions using dynamical mean-field theory. As an application we study the electrical response of the Falicov-Kimball model during the ultrafast buildup of the gapped phase at large interaction.