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arXiv · 1012.3581

Fractional quantum Hall effect in a U(1)xSU(2) gauge field

Rebecca N. Palmer·Jiannis K. Pachos
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Abstract

We consider the bosonic fractional quantum Hall effect in the presence of a non-Abelian gauge field in addition to the usual Abelian magnetic field. The non-Abelian field breaks the twofold internal state degeneracy, but preserves the Landau level degeneracy. Using exact diagonalization, we find that for moderate non-Abelian field strengths the system's behaviour resembles a single internal state quantum Hall system, while for stronger fields there is a phase transition to either two internal state behaviour or the complete absence of fractional quantum Hall plateaus. Usually the energy gap is reduced by the presence of a non-Abelian field, but some non-Abelian fields appear to slightly increase the gap of the $ν=1$ and $ν=3/2$ Read-Rezayi states.

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Rebecca N. Palmer, Jiannis K. Pachos. 2010-12-16. Fractional quantum Hall effect in a U(1)xSU(2) gauge field. https://doi.org/10.1088/1367-2630%2F13%2F6%2F065002

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