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Weak localisation, hole-hole interactions and the "metal"-insulator transition in two dimensions

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

A detailed investigation of the metallic behaviour in high quality GaAs-AlGaAs two dimensional hole systems reveals the presence of quantum corrections to the resistivity at low temperatures. Despite the low density ($r_{s}>10$) and high quality of these systems, both weak localisation (observed via negative magnetoresistance) and weak hole-hole interactions (giving a correction to the Hall constant) are present in the so-called metallic phase where the resistivity decreases with decreasing temperature. The results suggest that even at high $r_{s}$ there is no metallic phase at T=0 in two dimensions.

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M. Y. Simmons, A. R. Hamilton, M. Pepper, E. H. Linfield, P. D. Rose, D. A. Ritchie, .. 1999-10-24. Weak localisation, hole-hole interactions and the "metal"-insulator transition in two dimensions. https://doi.org/10.1103/physrevlett.84.2489

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