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arXiv · 1312.2396

Chern band insulators in magnetic field

Miguel A. N. Araújo·Eduardo V. Castro
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Abstract

The effect of a magnetic field on a two-dimensional Chern band insulator is discussed. It is shown that, unlike the trivial insulator, an anomalous Hall insulator with Chern number $C$ becomes a metal when a magnetic field is applied at constant particle density, for any $C>0$. For a time reversal invariant topological insulator with a spin Chern resolved number, $C_\uparrow= - C_\downarrow=C$, the magnetic field induces a spin polarized spin Hall insulator. We consider also the effect of a superlattice potential and extend previous results for the quantization of the Hall conductance of filled Hofstadter bands to this problem.

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Miguel A. N. Araújo, Eduardo V. Castro. 2013-12-09. Chern band insulators in magnetic field. https://doi.org/10.1088/0953-8984%2F26%2F7%2F075501

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