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

E. Ribeiro·R. Jaeggi·T. Heinzel·K. Ensslin·G. Medeiros-Ribeiro·P. M. Petroff
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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.

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E. Ribeiro, R. Jaeggi, T. Heinzel, K. Ensslin, G. Medeiros-Ribeiro, P. M. Petroff. 1998-08-27. Metal-Insulator Transition in a Disordered Two-Dimensional Electron Gas in GaAs-AlGaAs at zero Magnetic Field. https://doi.org/10.1103/physrevlett.82.996

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