Metal-Insulator Transition in a Disordered Two-Dimensional Electron Gas in GaAs-AlGaAs at zero Magnetic Field

TL;DR

This paper reports the observation of a metal-insulator transition at zero magnetic field in a disordered two-dimensional electron gas within GaAs-AlGaAs heterostructures, highlighting the role of disorder over electron interactions.

Contribution

It demonstrates a metal-insulator transition in a 2D electron gas with embedded quantum dots, emphasizing disorder's influence at zero magnetic field.

Findings

Transition occurs at resistances around h/e^2

Critical carrier density is approximately 1.2×10^11cm^-2

Electron-electron interactions are weak in the studied samples

Abstract

A metal-insulator transition in two-dimensional electron gases at B=0 is found in Ga(Al)As heterostructures, where a high density of self-assembled InAs quantum dots is incorporated just 3 nm below the heterointerface. The transition occurs at resistances around h/e^2 and critical carrier densities of 1.2 10^11cm^-2. Effects of electron-electron interactions are expected to be rather weak in our samples, while disorder plays a crucial role.