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Metal-insulator transition at B=0 in a dilute two dimensional GaAs-AlGaAs hole gas

M. Y. Simmons·A. R. Hamilton·M. Pepper·E. H. Linfield·P. D. Rose·D. A. Ritchie
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Abstract

We report the observation of a metal insulator transition at B=0 in a high mobility two dimensional hole gas in a GaAs-AlGaAs heterostructure. A clear critical point separates the insulating phase from the metallic phase, demonstrating the existence of a well defined minimum metallic conductivity sigma(min)=2e/h. The sigma(T) data either side of the transition can be `scaled' on to one curve with a single parameter (To). The application of a parallel magnetic field increases sigma(min) and broadens the transition. We argue that strong electron-electron interactions (rs = 10) destroy phase coherence, removing quantum intereference corrections to the conductivity.

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M. Y. Simmons, A. R. Hamilton, M. Pepper, E. H. Linfield, P. D. Rose, D. A. Ritchie. 1997-10-12. Metal-insulator transition at B=0 in a dilute two dimensional GaAs-AlGaAs hole gas. https://doi.org/10.1103/physrevlett.80.1292

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