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Double-layer quantum Hall antiferromagnetism at filling fraction nu=2/(odd integer)

S. Das Sarma·Subir Sachdev·Lian Zheng
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Abstract

A low energy action for double-layer quantum Hall systems at filling fractions $ν= 2/m$ ($m$ an odd integer) is introduced. Interlayer antiferromagnetic exchange induces a phase with canted spin order, and also a spin-singlet phase. Universal properties of zero and finite temperature transitions are obtained. We compute the critical temperature at which the canted order vanishes in a Kosterlitz-Thouless transition. Implications for recent light scattering experiments at $ν= 2$ are noted.

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S. Das Sarma, Subir Sachdev, Lian Zheng. 1997-01-21. Double-layer quantum Hall antiferromagnetism at filling fraction nu=2/(odd integer). https://doi.org/10.1103/physrevlett.79.917

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