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Electron correlation in the second Landau level; a competition between many, nearly degenerate quantum phases

J. S. Xia·W. Pan·C. L. Vincente·E. D. Adams·N. S. Sullivan·H. L. Stormer·D. C. Tsui·L. N. Pfeiffer·K. W. Baldwin·K. W. West
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Abstract

At a very low temperature of 9mK, electrons in the 2nd Landau level of an extremely high mobility two-dimensional electron system exhibit a very complex electronic behavior. With varying filling factor, quantum liquids of different origins compete with several insulating phases leading to an irregular pattern in the transport parameters. We observe a fully developed $ν=2+2/5$ state separated from the even-denominator $ν=2+1/2$ state by an insulating phase and a $ν=2+2/7$ and $ν=2+1/5$ state surrounded by such phases. A developing plateau at $ν=2+3/8$ points to the existence of other even-denominator states.

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J. S. Xia, W. Pan, C. L. Vincente, E. D. Adams, N. S. Sullivan, H. L. Stormer, D. C. Tsui, L. N. Pfeiffer, K. W. Baldwin, K. W. West. 2004-06-29. Electron correlation in the second Landau level; a competition between many, nearly degenerate quantum phases. https://doi.org/10.1103/physrevlett.93.176809

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