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arXiv · 1306.4154

The spin-polarized $\nu=0$ state of graphene: a spin superconductor

Qing-feng Sun·X. C. Xie
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Abstract

We study the spin-polarized $\nu=0$ Landau-level state of graphene. Due to the electron-hole attractive interaction, electrons and holes can bound into pairs. These pairs can then condense into a spin-triplet superfluid ground state: a spin superconductor state. In this state, a gap opens up in the edge bands as well as in the bulk bands, thus it is a charge insulator, but it can carry the spin current without dissipation. These results can well explain the insulating behavior of the spin-polarized $\nu=0$ state in the recent experiments.

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Qing-feng Sun, X. C. Xie. 2013-06-18. The spin-polarized $\nu=0$ state of graphene: a spin superconductor. https://doi.org/10.1103/physrevb.87.245427

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