The Electron-Glass in samples approaching the Mesoscopic regime

TL;DR

This study investigates how the electron-glass properties in indium-oxide films vary with sample size, revealing that certain mesoscopic effects diminish with size while fundamental glassy behaviors remain consistent down to micron scales.

Contribution

It demonstrates that electron-glass characteristics persist in mesoscopic samples and are unaffected by conductance fluctuations, providing new insights into size-dependent electron-glass phenomena.

Findings

Conductance fluctuations decrease with sample volume.

Electron-glass relaxation dynamics are size-independent down to 2 microns.

Glass features like slow relaxation and memory effects are consistent across sizes.

Abstract

We study the dependence of the glassy properties of strongly localized indium-oxide films on the sample lateral dimensions. Characteristic mesoscopic effects such as reproducible conductance fluctuations (CF) are readily observable in gated structures for sample size smaller than 100 microns measured at 4K, and the relative amplitude of the CF decreases with the sample volume as does the flicker noise. By contrast, down to sample size of few microns, the non-equilibrium features that are attributed to the electron-glass are indistinguishable from those observed in macroscopic samples, and in particular, the relaxation dynamics is independent of sample size down to 2 microns. In addition, The usual features that characterize the electron-glass including slow-relaxation, memory effects, and full-aging behavior are all observed in the `mesoscopic' regime, and they appear to be independent of the conductance fluctuations.