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Supersymmetry and Correlated Electrons in Graphene Quantum Hall Effect

Motohiko Ezawa
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Abstract

We present a supersymmetric description of the quantum Hall effect (QHE) in graphene. The noninteracting system is supersymmetric separately at the so-called K and K' points of the Brillouin zone corners. Its essential consequence is that the energy levels and the Landau levels are different objects in graphene QHE. Each energy level has a four-fold degeneracy within the noninteracting theory. With the Coulomb interaction included, an excitonic gap opens in the zero-energy state, while each nonzero energy level splits into two levels since up-spin and down-spin electrons come from different Landau levels. We argue the emergence of the plateaux at $ν=\pm (4n-2)$ for small magnetic field $B$ and at $ν=0$, $\pm 1$, $\pm 2n$ for large $B$ with $n$ natural numbers.

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Motohiko Ezawa. 2006-09-24. Supersymmetry and Correlated Electrons in Graphene Quantum Hall Effect. https://doi.org/10.1016/j.physe.2007.06.038

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