Quantum and classical phase transitions in double-layer quantum Hall ferromagnets

Lian Zheng

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arXiv · cond-mat/9703117

Quantum and classical phase transitions in double-layer quantum Hall ferromagnets

Lian Zheng

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Abstract

We consider the problem of quantum and classical phase transitions in double-layer quantum Hall systems at $\nu=1/m$ (m odd integers) from a long-wavelength statistical mechanics viewpoint. We derive an explicit mapping of the long-wavelength Lagrangian of the quantum Hall system into that of a three-dimensional isotropic classical XY model whose coupling constant depends on the quantum fluctuation in the original quantum Hall Hamiltonian. Universal properties of the quantum phase transition at the critical layer separation are completely determined by this mapping. The dependence of the Kosterlitz-Thouless transition temperature on layer separation, including quantum fluctuation effects, is approximately obtained by simple finite-size scaling analyses.

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Lian Zheng. 1997-03-12. Quantum and classical phase transitions in double-layer quantum Hall ferromagnets. https://arxiv.org/abs/cond-mat/9703117

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