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arXiv · 1306.6824

From dia- to paramagnetic orbital susceptibility of Dirac cones

A. Raoux·M. Morigi·J. N. Fuchs·F. Piéchon·G. Montambaux
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Abstract

We study the orbital susceptibility of coupled energy bands with a pair of Dirac points, as in graphene. We show that different systems having the same zero-field energy spectrum exhibit strong differences in their orbital magnetic response at zero energy, ranging from diamagnetism (graphene) to paramagnetism (dice lattice). A lattice model is introduced which interpolates continuously between these two limits. This striking behavior is related to a Berry phase varying continuously from pi to 0. These predictions could be tested with cold atoms in an optical lattice

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A. Raoux, M. Morigi, J. N. Fuchs, F. Piéchon, G. Montambaux. 2013-06-28. From dia- to paramagnetic orbital susceptibility of Dirac cones. https://doi.org/10.1103/physrevlett.112.026402

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