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Role of density imbalance in an interacting bilayer hole system

E. Tutuc·S. Melinte·E. P. De Poortere·R. Pillarisetty·M. Shayegan
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Abstract

We study interacting GaAs hole bilayers in the limit of zero tunneling. When the layers have equal densities, we observe a phase coherent bilayer quantum Hall (QH) state at total filling factor $ν=1$, flanked by insulating phases at nearby fillings which suggest the formation of a pinned, bilayer Wigner crystal. As we transfer charge from one layer to another, the insulating phases disappear while, surprisingly, the $ν=1$ QH state becomes stronger. Concomitantly, a pronounced hysteresis develops in the longitudinal magnetoresistance at higher fillings, indicative of a first-order quantum phase transition.

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E. Tutuc, S. Melinte, E. P. De Poortere, R. Pillarisetty, M. Shayegan. 2003-06-05. Role of density imbalance in an interacting bilayer hole system. https://doi.org/10.1103/physrevlett.91.076802

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