Dynamics of photo-doped charge transfer insulators

TL;DR

This paper investigates the nonequilibrium dynamics of charge-transfer insulators after photo-excitation, using advanced modeling techniques to match experimental observations and explore optical control of correlations.

Contribution

It introduces a nonequilibrium extension of Hartree-Fock+EDMFT and GW+EDMFT for realistic modeling of photo-doped charge-transfer insulators.

Findings

Renormalization of charge transfer gap and p bands after photo-doping

Broadening of bands observed in simulations

Qualitative agreement with experimental spectra

Abstract

We study the dynamics of charge-transfer insulators after photo-excitation using the three-band Emery model and a nonequilibrium extension of Hartree-Fock+EDMFT and GW+EDMFT. While the equilibrium properties are accurately reproduced by the Hartree-Fock treatment of the full $p$ bands, dynamical correlations are essential for a proper description of the photo-doped state. The insertion of doublons and holons leads to a renormalization of the charge transfer gap %and $p$ bands and to a substantial broadening of the bands. We calculate the time-resolved photoemission spectrum and optical conductivity and find qualitative agreement with experiments. Our formalism enables the realistic description of nonequilibrium phenomena in a large class of charge-transfer insulators, and provides a tool to explore the optical manipulation of interaction and correlation effects.