New Insights into the Plateau-InsulatorTransition in the Quantum Hall Regime
نویسنده
چکیده
We have measured the quantum critical behavior of the plateau-insulator (PI) transition in a low-mobility InGaAs/GaAs quantum well. The longitudinal resistivity measured for two different values of the electron density follows an exponential law, from which we extract critical exponents κ = 0.54 and 0.58, in good agreement with the value (κ = 0.57) previously obtained for an InGaAs/InP heterostructure. This provides evidence for a non-Fermi liquid critical exponent. By reversing the direction of the magnetic field we find that the averaged Hall resistance remains quantized at the plateau value h/e through the PI transition. From the deviations of the Hall resistance from the quantized value, we obtain the corrections to
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تاریخ انتشار 2003