Ultrafast hot carrier dynamics of ZrTe$_5$ from time-resolved optical reflectivity

TL;DR

This study explores the ultrafast hot carrier dynamics in ZrTe$_5$ using time-resolved optical reflectivity, revealing complex relaxation processes and the influence of many-body effects on its transient behavior.

Contribution

It provides new insights into the phonon-mediated recombination and complex electron thermalization processes in ZrTe$_5$, highlighting the role of many-body effects.

Findings

Phonon-mediated across-gap recombination observed.

Two distinct relaxation processes identified.

Many-body effects significantly influence transient dynamics.

Abstract

We investigate the hot carrier dynamics of ZrTe$_5$ by ultrafast time-resolved optical reflectivity. Our results reveal a phonon-mediated across-gap recombination, consistent with its temperature-dependent gap nature as observed previously by photoemission. In addition, two distinct relaxations with a kink feature right after initial photoexcitation are well resolved, suggesting the complexity of electron thermalization process. Our findings indicate that correlated many-body effects play important role for the transient dynamics of ZrTe$_5$.