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arXiv:1304.2856 · Physical Review B

Single-mode approximation for quantum Hall states with broken rotational symmetry

Ruizhi Qiu, Zi-Xiang Hu, Xin Wan

Published Dec 17, 2013• 5 citations
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Abstract

A topological phase can often be represented by a corresponding wave function (exact eigenstate of a model Hamiltonian) that has a higher underlying symmetry than necessary. When the symmetry is explicitly broken in the Hamiltonian, the model wave function fails to account for the change due to the lack of a variational parameter. Here we exemplify the case by an integer quantum Hall system with anisotropic interaction. We show that the single-mode approximation can introduce a variational parameter for a better description of the ground state, which is consistent with the recently proposed geometric description of the quantum Hall phases.

DOI
10.1103/physrevb.88.235118

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