Multiple Avalanches Across the Metal-Insulator Transition of Vanadium Oxide Nano-scaled Junctions

TL;DR

This study investigates the abrupt resistance jumps during the metal-insulator transition in nano-scaled VO2 devices, revealing avalanche behavior, power law distributions, and size-dependent effects, with a percolation model explaining general trends but not the statistical properties.

Contribution

It uncovers avalanche phenomena and power law distributions in VO2 nano-devices, highlighting size effects and limitations of existing models in explaining statistical behavior.

Findings

Resistance jumps span over 2 decades in amplitude.

Jump amplitudes follow a power law distribution.

Device size influences the transition behavior.

Abstract

The metal insulator transition of nano-scaled $VO_2$ devices is drastically different from the smooth transport curves generally reported. The temperature driven transition occurs through a series of resistance jumps ranging over 2 decades in amplitude, indicating that the transition is caused by avalanches. We find a power law distribution of the jump amplitudes, demonstrating an inherent property of the $VO_2$ films. We report a surprising relation between jump amplitude and device size. A percolation model captures the general transport behavior, but cannot account for the statistical behavior.