The conductivity and mobility of 2D nondegenerate electrons in the strong localization regime

P. W. Adams, Louisiana State University


We report magnetoconductance measurements of a nondegenerate 2D electron gas as a function of ambient helium gas density at several temperatures between T = 2 and 8 K. For helium gas densities greater than 2 × 1020 cm-3 the 2D electron gas is driven into a strong localization regime characterized by an activated conductivity with an activation energy proportional to the gas density. Magnetoresistance measurements at high gas densities show a remnant electron mobility consistent with an electron diffusivity of h{stroke}/mel at the mobility edge. © 1992.