Non-thermal light-assisted resistance collapse in a V$_2$O$_3$-based Mott-insulator device

TL;DR

This study demonstrates that ultrashort light pulses combined with voltage can induce a non-thermal, volatile resistivity drop in a V$_2$O$_3$ Mott insulator device, advancing control protocols for electronic phase transitions.

Contribution

It reveals a non-thermal, light-assisted method to induce resistive switching in V$_2$O$_3$ devices, surpassing thermal effects and enabling new control strategies.

Findings

Light pulses plus voltage cause a resistivity drop beyond thermal effects.

The resistive change is volatile and non-thermal.

Finite-element simulations support the experimental observations.

Abstract

The insulator-to-metal transition in Mott insulators is the key mechanism for a novel class of electronic devices, belonging to the Mottronics family. Intense research efforts are currently devoted to the development of specific control protocols, usually based on the application of voltage, strain, pressure and light excitation. The ultimate goal is to achieve the complete control of the electronic phase transformation, with dramatic impact on the performance, for example, of resistive switching devices. Here, we investigate the simultaneous effect of external voltage and excitation by ultrashort light pulses on a single Mottronic device based on a V$_2$O$_3$ epitaxial thin film. The experimental results, supported by finite-element simulations of the thermal problem, demonstrate that the combination of light excitation and external electrical bias drives a volatile resistivity drop which goes beyond the combined effect of laser and Joule heating. Our results impact on the development of protocols for the non-thermal control of the resistive switching transition in correlated materials.