Logarithmic relaxation and stress aging in the electron glass

Abstract

Slow relaxation and aging of the conductance are experimental features of a range of materials, which are collectively known as electron glasses. We report dynamic Monte Carlo simulations of the standard electron glass lattice model. In a non-equilibrium state, the electrons will often form a Fermi distribution with an effective electron temperature higher than the phonon bath temperature. We study the effective temperature as a function of time in three different situations: relaxation after a quench from an initial random state, during driving by an external electric field and during relaxation after such driving. We observe logarithmic relaxation of the effective temperature after a quench from a random initial state as well as after driving the system for some time $t_w$ with a strong electric field. For not too strong electric field and not too long $t_w$ we observe that data for the effective temperature at different waiting times collapse when plotted as functions of $t/t_w$ -- the so-called simple aging. During the driving period we study how the effective temperature is established, separating the contributions from the sites involved in jumps from those that were not involved. It is found that the heating mainly affects the sites involved in jumps, but at strong driving, also the remaining sites are heated.

References in corpus (18)

• Onset of Glassy Dynamics in a Two-Dimensional Electron System in Silicon
• Coulomb Gap: How a Metal Film Becomes an Insulator
• The glass transition and the Coulomb gap in electron glasses
• Stress-aging in the electron-glass
• The Memory Effect in Electron Glasses
• Many electron theory of 1/f-noise in hopping conductivity
• History-dependent relaxation and the energy scale of correlation in the Electron-Glass
• Long time relaxation of interacting electrons in the regime of hopping conduction
• Electrical properties of isotopically enriched neutron-transmutation-doped ^{70} Ge:Ga near the metal-insulator transition
• Slow conductance relaxations; Distinguishing the Electron Glass from extrinsic mechanisms
• Nonexponential Relaxations in a Two-Dimensional Electron System in Silicon
• Influence of parallel magnetic fields on a single-layer two-dimensional electron system with a hopping mechanism of conductivity
• Huge (but finite) time scales in slow relaxations: beyond simple aging
• Ultrafast (but Many-Body) Relaxation in a Low-Density Electron Glass
• Dielectric susceptibility of the Coulomb-glass
• Effects of many-electron jumps in relaxation and conductivity of Coulomb glasses
• Slow Relaxation and Equilibrium Dynamics in a 2 D Coulomb Glass: Demonstration of Stretched Exponential Energy Correlations
• Nonlinear conductivity of two-dimensional Coulomb glasses

Cited by in corpus (6)

• Dimensionality Dependence of Aging in Kinetics of Diffusive Phase Separation: Behavior of order-parameter autocorrelation
• Effects of Density Conservation and Hydrodynamics on Aging in Nonequilibrium Processes
• Thermalization Processes in Interacting Anderson Insulators
• Coexistence of Electron-Glass Phase and Persistent Photoconductivity in GeSbTe Compounds
• Electron glass signatures up to room temperature in disordered insulators
• Low frequency excitations in the Coulomb Glass: numerical analysis using the avalanche method