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arXiv · 1904.03159

Two- and three-electron bubbles in Al$_{x}$Ga$_{1-x}$As/Al$_{0.24}$Ga$_{0.76}$As quantum wells

X. Fu·Q. Shi·M. A. Zudov·G. C. Gardner·J. D. Watson·M. J. Manfra
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Abstract

We report on transport signatures of eight distinct bubble phases in the $N=3$ Landau level of a Al$_{x}$Ga$_{1-x}$As/Al$_{0.24}$Ga$_{0.76}$As quantum well with $x = 0.0015$. These phases occur near partial filling factors $ν^\star \approx 0.2\,(0.8)$ and $ν^\star \approx 0.3\,(0.7)$ and have $M = 2$ and $M = 3$ electrons (holes) per bubble, respectively. We speculate that a small amount of alloy disorder in our sample helps to distinguish these broken symmetry states in low-temperature transport measurements.

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X. Fu, Q. Shi, M. A. Zudov, G. C. Gardner, J. D. Watson, M. J. Manfra. 2019-04-05. Two- and three-electron bubbles in Al$_{x}$Ga$_{1-x}$As/Al$_{0.24}$Ga$_{0.76}$As quantum wells. https://doi.org/10.1103/physrevb.99.161402

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