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arXiv · 1005.5121

Atypical Fractional Quantum Hall Effect in Graphene at Filling Factor 1/3

Z. Papic·M. O. Goerbig·N. Regnault
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Abstract

We study the recently observed graphene fractional quantum Hall state at a filling factor $ν_G=1/3$ using a four-component trial wave function and exact diagonalization calculations. Although it is adiabatically connected to a 1/3 Laughlin state in the upper spin branch, with SU(2) valley-isospin ferromagnetic ordering and a completely filled lower spin branch, it reveals physical properties beyond such a state that is the natural ground state for a large Zeeman effect. Most saliently, it possesses at experimentally relevant values of the Zeeman gap low-energy spin-flip excitations that may be unveiled in inelastic light-scattering experiments.

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Z. Papic, M. O. Goerbig, N. Regnault. 2010-10-21. Atypical Fractional Quantum Hall Effect in Graphene at Filling Factor 1/3. https://doi.org/10.1103/physrevlett.105.176802

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