Topological Mid-gap States of Topological Insulators with Flux-Superlattice

Ya-Jie Wu; Jing He; Su-Peng Kou

doi:10.1209/0295-5075/105/47002

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arXiv · 1312.4360

Topological Mid-gap States of Topological Insulators with Flux-Superlattice

Ya-Jie Wu·Jing He·Su-Peng Kou

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Abstract

In this paper based on the Haldane model, we study the topological insulator with superlattice of pi-fluxes. We find that there exist the mid-gap states induced by the flux-superlattice. In particular, the mid-gap states have nontrivial topological properties, including the nonzero Chern number and the gapless edge states. We derive an effective tight-binding model to describe the topological midgap states and then study the mid-gap states by the effective tight-binding model. The results can be straightforwardly generalized to other two dimensional topological insulators with flux-superlattice.

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Ya-Jie Wu, Jing He, Su-Peng Kou. 2013-12-16. Topological Mid-gap States of Topological Insulators with Flux-Superlattice. https://doi.org/10.1209/0295-5075%2F105%2F47002

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