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New insulating phases of two-dimensional electrons in high Landau levels: observation of sharp thresholds to conduction

K. B. Cooper·M. P. Lilly·J. P. Eisenstein·L. N. Pfeiffer·K. W. West
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Abstract

The intriguing re-entrant integer quantized Hall states recently discovered in high Landau levels of high-mobility 2D electron systems are found to exhibit extremely non-linear transport. At small currents these states reflect insulating behavior of the electrons in the uppermost Landau level. At larger currents, however, a discontinuous and hysteretic transition to a conducting state is observed. These phenomena, found only in very narrow magnetic field ranges, are suggestive of the depinning of a charge density wave state, but other explanations can also be constructed.

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K. B. Cooper, M. P. Lilly, J. P. Eisenstein, L. N. Pfeiffer, K. W. West. 1999-07-23. New insulating phases of two-dimensional electrons in high Landau levels: observation of sharp thresholds to conduction. https://doi.org/10.1103/physrevb.60.r11285

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