Nonequilibrium Relaxations and Aging Effects in a Two-Dimensional Coulomb Glass

TL;DR

This study investigates the aging and relaxation behaviors of conductivity in a disordered 2D electron system in Si, revealing conditions for monotonic aging and nonmonotonic memory loss in glassy regimes.

Contribution

It identifies the conditions under which conductivity relaxations in a 2D Coulomb glass exhibit aging or memory loss, advancing understanding of nonequilibrium dynamics.

Findings

Aging behavior depends on waiting time and temperature.

Memory effects are lost under certain conditions.

Distinct regimes of monotonic and nonmonotonic relaxation identified.

Abstract

The relaxations of conductivity have been studied in the glassy regime of a strongly disordered two-dimensional electron system in Si after a temporary change of carrier density during the waiting time t_w. Two types of response have been observed: a) monotonic, where relaxations exhibit aging, i.e. dependence on history, determined by t_w and temperature; b) nonmonotonic, where a memory of the sample history is lost. The conditions that separate the two regimes have been also determined.