Phase Diagram for Quantum Hall Bilayers at 1
نویسندگان
چکیده
116802-1 We present a phase diagram for a double quantum well bilayer electron gas in the quantum Hall regime at a total filling factor 1, based on exact numerical calculations of the topological Chern number matrix and the (interlayer) superfluid density. We find three phases: a quantized Hall state with pseudospin superfluidity, a quantized Hall state with pseudospin ‘‘gauge-glass’’ order, and a decoupled composite Fermi liquid. Comparison with experiments provides a consistent explanation of the observed quantum Hall plateau, Hall drag plateau, and vanishing Hall drag resistance, as well as the zero-bias conductance peak effect, and suggests some interesting points to pursue experimentally.
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