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arXiv · 1806.04382

Interaction induced edge states in HgTe/CdTe Quantum Well under magnetic field

Zewei Chen·Tai Kai Ng
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Abstract

In this paper, we study doped HgTe/CdTe quantum well with Hubbard-type interaction under perpendicular magnetic field using a lattice Bernevig-Hughes-Zhang (BHZ) model with a bulk inversion asymmetry (BIA) term. We show that the BIA term is strongly enhanced by interaction around the region when the band inversion of the topological insulator is destroyed by a magnetic field. The enhanced BIA term creates edge-like electronic states which can explain the experimentally discovered edge conductance in doped HgTe/CdTe quantum well at similar magnetic field regime.

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Zewei Chen, Tai Kai Ng. 2018-06-12. Interaction induced edge states in HgTe/CdTe Quantum Well under magnetic field. https://doi.org/10.1103/physrevb.99.235157

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