arXiv 1306.68242013-06-28cond-mat.mes-hall

From dia- to paramagnetic orbital susceptibility of Dirac cones

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

备注：: 5 pages, 10 figures, supplementary material
发表信息：: Phys. Rev. Lett. 112, 026402 (2014)
DOI：: 10.1103/PhysRevLett.112.026402

英文摘要：

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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