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arXiv · 1105.5270

Multi-component fractional quantum Hall states in graphene: SU(4) versus SU(2)

Csaba Toke·Jainendra K. Jain
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Abstract

Because of the spin and Dirac-valley degrees of freedom, graphene allows the observation of one-, two- or four-component fractional quantum Hall effect in different parameter regions. We argue that some, though not all, apparently puzzling features observed in recent experiments are consistent with a two-component fractional quantum Hall effect, with the electron spin frozen but the Dirac-valley symmetry approximately intact. In the SU(4) limit, we predict that new low-energy Goldstone modes determine the stability of the fractional quantum Hall states at 2/5, 3/7 etc.; SU(4) skyrmions are not relevant for the low-energy physics.

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Csaba Toke, Jainendra K. Jain. 2012-05-23. Multi-component fractional quantum Hall states in graphene: SU(4) versus SU(2). https://doi.org/10.1088/0953-8984%2F24%2F23%2F235601

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