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arXiv · 1007.3006

Composite fermion dynamics in half-filled Landau levels of graphene

Arkadiusz Wojs·Gunnar Moller·Nigel R. Cooper
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Abstract

We report on exact-diagonalization studies of correlated many-electron states in the half-filled Landau levels of graphene, including pseudospin (valley) degeneracy. We demonstrate that the polarized Fermi sea of non-interacting composite fermions remains stable against a pairing transition in the lowest two Landau levels. However, it undergoes spontaneous depolarization, which is unprotected owing to the lack of single-particle pseudospin splitting. These results suggest the absence of the Pfaffian phase in graphene.

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Arkadiusz Wojs, Gunnar Moller, Nigel R. Cooper. 2010-07-18. Composite fermion dynamics in half-filled Landau levels of graphene. https://arxiv.org/abs/1007.3006

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