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Competition Between Fractional Quantum Hall Liquid, Bubble and Wigner Crystal Phases in the Third Landau Level

G. Gervais·L. W. Engel·H. L. Stormer·D. C. Tsui·K. W. Baldwin·K. W. West·L. N. Pfeiffer
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Abstract

Magnetotransport measurements were performed in a ultra-high mobility GaAs/AlGaAs quantum well of density $\sim 3.0 \times 10^{11}$ $cm^{-2}$. The temperature dependence of the magnetoresistance $R_{xx}$ was studied in detail in the vicinity of $ν={9/2}$. In particular, we discovered new minima in $R_{xx}$ at filling factor $ν\simeq 4{1/5}$ and $4{4/5}$, but only at intermediate temperatures $80\lesssim T\lesssim 120$ mK. We interpret these as evidence for a fractional quantum Hall liquid forming in the N=2 Landau level and competing with bubble and Wigner crystal phases favored at lower temperatures. Our data suggest that a magnetically driven insulator-insulator quantum phase transition occurs between the bubble and Wigner crystal phases at T=0.

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G. Gervais, L. W. Engel, H. L. Stormer, D. C. Tsui, K. W. Baldwin, K. W. West, L. N. Pfeiffer. 2004-12-21. Competition Between Fractional Quantum Hall Liquid, Bubble and Wigner Crystal Phases in the Third Landau Level. https://doi.org/10.1103/physrevlett.93.266804

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