Photoconduction and photocontrolled collective effects in the Peierls conductor TaS$_3$

TL;DR

This paper investigates how light illumination affects the electrical conduction and collective charge density wave (CDW) behavior in TaS$_3$, revealing significant changes in linear and nonlinear conduction, including increased elasticity and hysteresis.

Contribution

It demonstrates that illumination enhances CDW elasticity and induces switching and hysteresis in nonlinear conduction, revealing new light-controlled collective effects in TaS$_3$.

Findings

Light increases linear conductance G in TaS$_3$.

Illumination suppresses collective conduction and raises the threshold field E_T.

A relation E_T ∝ G^{1/3} is observed, consistent with one-dimensional pinning.

Abstract

Light illumination of thin crystals of CDW conductor TaS$_3$ is found to result in dramatic changes of both linear ($G$) and nonlinear conduction. The increase of $G$ is accompanied by suppression of the collective conduction, growth of the threshold field $E_T$, and appearance of the switching and hysteretic behavior in the nonlinear conduction. The effects in the nonlinear conduction are associated with increase of CDW elasticity due to illumination that leads in particular to appearance of a relation $E_T\propto G^{1/3}$ expected for the one-dimensional pinning.