Tuesday, December 18, 2012

1212.4046 (Doru Sticlet et al.)

Distant-Neighbor Hopping in Graphene and Haldane Models    [PDF]

Doru Sticlet, Frédéric Piéchon
Large Chern number phases in Haldane model become possible if there is a multiplication of Dirac points in the underlying graphene model. This is realized by considering long distance hopping integrals. Through variation of these integrals, it is possible to arrive at super-merging band touchings, that up to N7 graphene are unique in parameter space. They result from the synchronized motion of all supplementary Dirac points into the regular +/-K points of graphene. The energy dispersion power law is usually larger then the topological charge associated to them. Moreover, adding distant-neighbor hoppings in the Haldane mass allows to sweep large number Chern phases in the topological insulator.
View original: http://arxiv.org/abs/1212.4046

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