Dielectric breakdown and avalanches at non-equilibrium metal-insulator transitions

TL;DR

This paper models the non-equilibrium metal-insulator transition in VO2 films as a dielectric breakdown process, revealing universal resistance jump characteristics and a critical point separating different avalanche behaviors.

Contribution

It introduces a classical coarse-grained model for the transition, capturing disorder effects and predicting a new critical point in avalanche dynamics.

Findings

Universal resistance jump distribution characterized.

Identification of a critical point separating avalanche regimes.

Prediction of voltage-tuned phase transition in avalanche behavior.

Abstract

Motivated by recent experiments on the finite temperature Mott transition in VO2 films, we propose a classical coarse-grained dielectric breakdown model where each degree of freedom represents a nanograin which transitions from insulator to metal with increasing temperature and voltage at random thresholds due to quenched disorder. We describe the properties of the resulting non-equilibrium metal-insulator transition and explain the universal characteristics of the resistance jump distribution. We predict that by tuning voltage, another critical point is approached, which separates a phase of "bolt"-like avalanches from percolation-like ones.