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arXiv · 0712.3085

Disappearance of the metal-like behavior in GaAs two-dimensional holes below 30 mK

Jian Huang·J. S. Xia·D. C. Tsui·L. N. Pfeiffer·K. W. West
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Abstract

The zero-field temperature-dependence of the resistivity of two-dimensional holes are observed to exhibit two qualitatively different characteristics for a fixed carrier density for which only the metallic behavior of the so-called metal-insulator transition is anticipated. As $T$ is lowered from 150 mK to 0.5 mK, the sign of the derivative of the resistivity with respect to $T$ changes from being positive to negative when the temperature is lowered below $\sim$30 mK and the resistivity continuously rises with cooling down to 0.5 mK, suggesting a crossover from being metal-like to insulator-like.

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Jian Huang, J. S. Xia, D. C. Tsui, L. N. Pfeiffer, K. W. West. 2007-12-19. Disappearance of the metal-like behavior in GaAs two-dimensional holes below 30 mK. https://doi.org/10.1103/physrevlett.98.226801

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