Non-Gaussian Resistance Noise near Electrical Breakdown in Granular Materials

TL;DR

This study uses numerical simulations to analyze resistance fluctuations in granular materials near electrical breakdown, revealing non-Gaussian behavior that persists near critical points and depends on system size and disorder.

Contribution

It demonstrates that non-Gaussian resistance fluctuations near breakdown are influenced by system size and disorder, and identifies the Bramwell-Holdsworth-Pinton distribution as a universal pattern at criticality.

Findings

Non-Gaussian resistance fluctuations increase with disorder.

Finite size effects cause Gaussian behavior away from criticality.

Universal Bramwell-Holdsworth-Pinton distribution describes fluctuations at criticality.

Abstract

The distribution of resistance fluctuations of conducting thin films with granular structure near electrical breakdown is studied by numerical simulations. The film is modeled as a resistor network in a steady state determined by the competition between two biased processes, breaking and recovery. Systems of different sizes and with different levels of internal disorder are considered. Sharp deviations from a Gaussian distribution are found near breakdown and the effect increases with the degree of internal disorder. However, we show that in general this non-Gaussianity is related to the finite size of the system and vanishes in the large size limit. Nevertheless, near the critical point of the conductor-insulator transition, deviations from Gaussianity persist when the size is increased and the distribution of resistance fluctuations is well fitted by the universal Bramwell-Holdsworth-Pinton distribution.