Hot carrier scaling of localization in a quantum dot array

The nonlinear conductivity of an array of quantum dots, formed by split-gat es on a GaAs/AlGaAs heterostructure, is studied. Previously, this array was shown to exhibit a gate bias-induced localization behavior at low temperat ures, similar to the insulating state found in 2D systems. Here, we study t he effect of source-drain bias potential on the heating of the electron sys tem in the dots. We find that the scaling of conductance with this bias vol tage can be described by an equation similar to that for temperature. In ad dition, we determine the effective temperature and energy-relaxation time. This relaxation time appears to decay as T-3/2 at higher temperatures, but shows a saturation at low temperatures. (C) 1999 Elsevier Science B.V. All rights reserved.