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Nonmonotonic Temperature-dependent Resistance in Low Density 2D Hole Gases

A. P. Mills, Jr.·A. P. Ramirez·L. N. Pfeiffer·K. W. West
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Abstract

The low temperature longitudinal resistance-per-square Rxx(T) in ungated GaAs/AlGaAs quantum wells of high peak hole mobility 1.7x10^6 cm^2/Vs is metallic for 2D hole density p as low as 3.8x10^9 cm-2. The electronic contribution to the resistance, R_{el}(T), is a nonmonotonic function of T, exhibiting thermal activation, R_{el}(T) ~ exp{-E_a/kT}, for kT< EF. The form of R_{el}(T) is independent of density, indicating a fundamental relationship between the low and high T scattering mechanisms in the metallic state.

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A. P. Mills, Jr., A. P. Ramirez, L. N. Pfeiffer, K. W. West. 1999-05-12. Nonmonotonic Temperature-dependent Resistance in Low Density 2D Hole Gases. https://doi.org/10.1103/physrevlett.83.2805

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