Disorder-driven stochastic dynamics in Mott resistive-switching systems

TL;DR

This study demonstrates that controlled disorder via ion beam irradiation in Mott insulators like VO2 and V2O3 induces stochastic oscillations and significantly lowers switching energy, offering new insights for neuromorphic hardware design.

Contribution

It reveals how defect-induced disorder transforms regular oscillations into stochastic firing in Mott resistive switches, supported by experiments and numerical simulations.

Findings

Irradiation induces stochastic firing in resistive oscillators.

Switching energy is reduced by orders of magnitude.

Experimental results match numerical simulations.

Abstract

Controlled disorder in correlated materials provides a new route to emergent stochastic dynamics in neuromorphic hardware. Here we show that focused ion beam irradiation in VO$_{2}$- and V$_{2}$O$_{3}$-based resistive-switching oscillators induces a transition from regular periodic oscillations to strongly irregular stochastic firing, while simultaneously reducing the required switching energy by orders of magnitude. Under an applied electric field, these materials undergo a volatile insulator-to-metal transition characterized by the formation of percolating metallic filaments within an insulating bulk. Using numerical simulations based on the Mott resistor network, we demonstrate that defect-induced modifications to filament nucleation and stability drive these devices into stochastic oscillatory regimes. These results are validated by experimental measurements on irradiated VO$_{2}$ and V$_{2}$O$_{3}$ devices.