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Fractional charges and quantum phase transitions in imbalanced bilayer quantum Hall systems

Jinwu Ye
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Abstract

We extend the Composite Boson theory to study slightly im-balanced bi-layer Quantum Hall systems. In the global $ U(1) $ symmetry breaking excitonic superfluid side, as the imbalance increases, the system supports continuously changing fractional charges. In the translational symmetry breaking pseudo-spin density wave (PSDW) side, there are two quantum phase transitions from the commensurate PSDW to an in-commensurate PSDW and then to the excitonic superfluid state. We compare our theory with experimental data and also the previous microscopic calculations.

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Jinwu Ye. 2006-10-25. Fractional charges and quantum phase transitions in imbalanced bilayer quantum Hall systems. https://doi.org/10.1103/physrevlett.97.236803

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