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arXiv · 1003.5931

Colossal anisotropy in diluted magnetic topological insulators

A. S. Núñez·J. Fernández-Rossier
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Abstract

We consider dilute magnetic doping in the surface of a three dimensional topological insulator where a two dimensional Dirac electron gas resides. We find that exchange coupling between magnetic atoms and the Dirac electrons has a strong and peculiar effect on both. First, the exchange-induced single ion magnetic anisotropy is very large and favors off-plane orientation. In the case of ferromagnetically ordered phase we find a colossal magnetic anisotropy energy, of the order of the critical temperature. Second, a persistent electronic current circulates around the magnetic atom and, in the case of a ferromagnetic phase, around the edges of the surface.

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A. S. Núñez, J. Fernández-Rossier. 2010-03-30. Colossal anisotropy in diluted magnetic topological insulators. https://doi.org/10.1016/j.ssc.2011.11.047

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