Scaling in plateau-to-plateau transition: a direct connection of quantum hall systems with the Anderson localization model.
The quantum Hall-plateau transition was studied at temperatures down to 1 mK in a random alloy disordered high mobility two-dimensional electron gas. A perfect power-law scaling with kappa=0.42 was observed from 1.2 K down to 12 mK. This perfect scaling terminates sharply at a saturation temperature of Ts approximately 10 mK. The saturation is identified as a finite-size effect when the quantum phase coherence length (Lphi proportional, T(-p/2)) reaches the sample size (W) of millimeter scale. From a size dependent study, Ts proportional, W(-1) was observed and p=2 was obtained. The exponent of the localization length, determined directly from the measured kappa and p, is nu=2.38, and the dynamic critical exponent z=1.
Li
Wanli
W
Princeton University, Princeton, New Jersey 08544, USA. sciwanli@gmail.com
Vicente
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Xia
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Pan
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Tsui
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Pfeiffer
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West
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