Transition to exponential relaxation in weakly-disordered electron-glasses

Abstract

The out-of-equilibrium excess conductance of electron-glasses typically relaxes with a logarithmic time-dependence. Here it is shown that the log(t) relaxation of a weakly-disordered amorphous indium-oxide films crosses-over asymptotically to an exponential dependence. This allows assigning a well-defined relaxation-time t' for a given system-disorder (characterized by the Ioffe-Regel parameter). Near the metal-insulator transition, t' obeys the scaling relation with the same critical disorder where the zero-temperature conductivity of this system vanishes. The latter defines the position of the disorder-driven metal-to-insulator transition (MIT) which is a quantum-phase-transition. In this regard the electron-glass differs from classical-glasses such as the structural-glass and spin-glass. The ability to experimentally assign an unambiguous relaxation-time allows us to demonstrate the steep dependence of the electron-glass dynamics on carrier-concentration.

6 pages and 7 figures

References in corpus (11)

• Logarithmic Relaxation in Glass-Forming Systems
• Compositional disorder and tranport peculiarities in the amorphous indium-oxides
• Relaxation dynamics in quantum electron-glasses
• A quench-cooling procedure compared with the gate-protocol for aging experiments in the Electron-Glass
• Anomalous diffusion and stretched exponentials in heterogeneous glass-forming liquids: Low-temperature behavior
• Slow Dynamics of the Electron-Glasses; the Role of Disorder
• Memory effects in transport through a hopping insulator: Understanding two-dip experiments
• Electron Glass in a three-dimensional system
• Memory vs. irreversibility in thermal densification of amorphous glasses
• Slow relaxation of conductance of amorphous hopping insulators
• Conductance relaxation in GeBiTe - slow thermalization in an open quantum system

Cited by in corpus (8)

• Screening the Coulomb interaction and thermalization of Anderson insulators
• Electron glass effects in amorphous NbSi films
• Relaxation dynamics of the three-dimensional Coulomb Glass model
• Interaction induced spatial correlations in a Disordered Glass
• Electron glass signatures up to room temperature in disordered insulators
• The effect of screening on the relaxation dynamics in the Coulomb glass
• Relaxation of the Random Site Coulomb glass Model in Two Dimensions
• Anomalous thermal activation of the electron glass dynamics in a-InOx and granular aluminum