Study of metal insulator transition: percolation-type in GaAs/AlGaAs 2D

Abstract

In this work the existence of a possible percolation transition in a dilute two dimensional hole gas in GaAs/AlGaAs within a parallel magnetic field at a fixed temperature T = 260mk is studied. Following the evolution of the electrical conductivity as a function of magnetic field at high carrier densities, we have showed the creation of a densitity inhomogeneity beyond the critical percolation leading to metallic side. These results were proved in the present article by studying the exponent characterizing the type of transition and the variation of the critical percolation densities, which are considered good indicators to observe the percolation transition. In this investigation, we have reanalyzed the data obtained by Kumar et al published in the reference [M. Kumar et al, Solid State Communications Vol. 135. pp. 57–61 (2005)].