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arXiv · 0807.2867

Onset of an Insulating Zero-Plateau Quantum Hall State in Graphene

Efrat Shimshoni·H. A. Fertig·G. Venketeswara Pai
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Abstract

We analyze the dissipative conductance of the zero-plateau quantum Hall state appearing in undoped graphene in strong magnetic fields. Charge transport in this state is assumed to be carried by a magnetic domain wall, which forms by hybridization of two counter--propagating edge states of opposing spin due to interactions. The resulting non--chiral edge mode is a Luttinger liquid of parameter K, which enters a gapped, perfectly conducting state below a critical value K_c\approx 1/2. Backscattering in this system involves spin flip, so that interaction with localized magnetic moments generates a finite resistivity R_{xx} via a "chiral Kondo effect". At finite temperatures T, R_{xx}(T) exhibits a crossover from metallic to insulating behavior as K is tuned across a threshold K_{MI}. For T->0, R_{xx} in the intermediate regime K_{MI}<K<K_c is finite, but diverges as K approaches K_c. This model provides a natural interpretation of recent experiments.

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Efrat Shimshoni, H. A. Fertig, G. Venketeswara Pai. 2009-05-06. Onset of an Insulating Zero-Plateau Quantum Hall State in Graphene. https://arxiv.org/abs/0807.2867

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