Possibility of magnetic field induced Composite Fermi sea in neutral Graphene

G. Baskaran

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arXiv · cond-mat/0702420

Possibility of magnetic field induced Composite Fermi sea in neutral Graphene

G. Baskaran

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Abstract

Neutral graphene in strong magnetic fields is believed to be an (exchange stabilized) integer Hall state of completely filled up spin (say) and empty down spin bands of n = 0, two fold valley degenerate Landau levels. We suggest that correlation energy gain from a nearly SU(4) singlet (2 spin $\times$ 2 valley) composite fermi sea formation, at $ν\approx$ \hlf filling for each component, destabilizes ferromagnetic integer quantum Hall state. This radically different scenario is consistent with a dissipative gapless state seen in experiments in neutral graphene. Interesting paired Hall states are possible, from residual interactions, in this SU(4) fermi sea with a small Zeeman spin polarization.

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G. Baskaran. 2007-02-18. Possibility of magnetic field induced Composite Fermi sea in neutral Graphene. https://arxiv.org/abs/cond-mat/0702420

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