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arXiv · 1111.5384

Observation of reentrant quantum Hall states in the lowest Landau level

Yang Liu·C. G. Pappas·M. Shayegan·L. N. Pfeiffer·K. W. West·K. W. Baldwin
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Abstract

Measurements in very low disorder two-dimensional electrons confined to relatively wide GaAs quantum well samples with tunable density reveal reentrant $\nu=1$ integer quantum Hall states in the lowest Landau level near filling factors $\nu=4/5$ and 6/5. These states are not seen at low densities and become more prominent with increasing density and in wider wells. Our data suggest a close competition between different types of Wigner crystal states near these fillings. We also observe an intriguing disappearance and reemergence of the $\nu=4/5$ fractional quantum Hall effect with increasing density.

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Yang Liu, C. G. Pappas, M. Shayegan, L. N. Pfeiffer, K. W. West, K. W. Baldwin. 2011-11-23. Observation of reentrant quantum Hall states in the lowest Landau level. https://doi.org/10.1103/physrevlett.109.036801

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