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arXiv · 1703.07086

Magnetic properties of 2D topological insulators

Zewei Chen·Tai Kai Ng
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Abstract

The effects of Hubbard-type on-site interactions on the BHZ model is studied in this paper for model parameters appropriate for the HgTe/CdTe quantum well. Within a simple mean field theory we search for plausible magnetic instabilities in the model and find that the ground state becomes {\em ferromagnetic} when the interaction strength between electrons in hole orbital is strong enough. The result can be understood by an approximate mapping of the Hubbard-BHZ model to the one band Hubbard model. The same mapping suggests that the magnetic and/or other ordered phases are more likely to occur in large gap topological insulators whose occupations are close to 1/2 for both electron and hole orbital.

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Zewei Chen, Tai Kai Ng. 2017-03-21. Magnetic properties of 2D topological insulators. https://arxiv.org/abs/1703.07086

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