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arXiv · 1609.09063

Interlayer Pairing Symmetry of Composite Fermions in Quantum Hall Bilayers

Hiroki Isobe·Liang Fu
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Abstract

We study the pairing symmetry of the interlayer paired state of composite fermions in quantum Hall bilayers. Based on the Halperin-Lee-Read (HLR) theory, the effect of the long-range Coulomb interaction and the internal Chern-Simons gauge fluctuation is analyzed with the random-phase approximation beyond the leading order contribution in small momentum expansion, and we observe that the interlayer paired states with a relative angular momentum $l=+1$ are energetically favored for filling $ν=\frac{1}{2}+\frac{1}{2}$ and $\frac{1}{4}+\frac{1}{4}$. The degeneracy between states with $\pm l$ is lifted by the interlayer density-current interaction arising from the interplay of the long-range Coulomb interaction and the Chern-Simons term in the HLR theory.

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Hiroki Isobe, Liang Fu. 2017-04-26. Interlayer Pairing Symmetry of Composite Fermions in Quantum Hall Bilayers. https://doi.org/10.1103/physrevlett.118.166401

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