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

الأصل · EN

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*10¹0 cm-2 on the metallic side of the zero-field 'metal-insulator transition' (MIT). In a parallel field well above Bc that suppresses the metallic conductivity, the 2DHG exhibits a conductivity g(T) 0.3(e²/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 Bc.