Photoinduced metallic properties of one-dimensional strongly correlated electron systems

TL;DR

This study investigates how photoexcitation can induce metallic properties in one-dimensional strongly correlated electron systems, revealing that light can effectively turn an insulator into a metal.

Contribution

It provides a detailed analysis of photoinduced metallic states in the 1D Hubbard model, showing spectral weight transfer similar to doping effects.

Findings

Photoexcited states exhibit large spectral weights including Drude weight below the optical gap.

Spectral weight above the optical gap is significantly reduced after photoexcitation.

Photoexcitation induces a metallic state similar to chemical doping.

Abstract

We study photoinduced optical responses of one-dimensional strongly correlated electron systems. The optical conductivity spectra are calculated for the ground state and a photoexcited state in the one-dimensional Hubbard model at half filling by using the exact diagonalization method. It is found that, in the Mott insulator phase, the photoexcited state has large spectral weights including the Drude weight below the optical gap. As a consequence, the spectral weight above the optical gap is largely reduced. These results imply that a metallic state is induced by photoexcitation. Comparison between the photoexcited and hole-doped states shows that the photoexcitation is similar to chemical doping.