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arXiv · 1302.2284

Single Dirac-Cone State and Quantum Hall Effects in Honeycomb Structure

Motohiko Ezawa
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Abstract

A honeycomb lattice system has four types of Dirac electrons corresponding to the spin and valley degrees of freedom. We consider a state that contains only one type of massless electrons and three types of massive ones, which we call the single Dirac-cone state. We analyze quantum Hall (QH) effects in this state. We make a detailed investigation of the Chern and spin-Chern numbers. We make clear the origin of unconventional QH effects discovered in graphene. We also show that the single Dirac-cone state may have arbitrary large spin-Chern numbers in magnetic field. Such a state will be generated in antiferromagnetic transition-metal oxides under electric field or silicene with antiferromagnetic order under electric field.

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Motohiko Ezawa. 2013-08-15. Single Dirac-Cone State and Quantum Hall Effects in Honeycomb Structure. https://doi.org/10.1209/0295-5075%2F104%2F27006

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