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The metallic resistance of a dilute two-dimensional hole gas in a GaAs quantum well: two-phase separation at finite temperature?

Xuan P. A. Gao·Allen P. Mills Jr.·Arthur P. Ramirez·Loren N. Pfeiffer·Kenneth W. West
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Abstract

We have studied the magnetotransport properties of a high mobility two-dimensional hole gas (2DHG) system in a 10nm GaAs quantum well (QW) with densities in range of 0.7-1.6*10^10 cm^-2 on the metallic side of the zero-field 'metal-insulator transition' (MIT). In a parallel field well above B_c that suppresses the metallic conductivity, the 2DHG exhibits a conductivity g(T)~0.3(e^2/h)lnT reminiscent of weak localization. The experiments are consistent with the coexistence of two phases in our system: a metallic phase and a weakly insulating Fermi liquid phase having a percolation threshold close to B_c.

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Xuan P. A. Gao, Allen P. Mills Jr., Arthur P. Ramirez, Loren N. Pfeiffer, Kenneth W. West. 2001-10-29. The metallic resistance of a dilute two-dimensional hole gas in a GaAs quantum well: two-phase separation at finite temperature?. https://doi.org/10.1103/physrevlett.89.016801

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