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arXiv · 1310.6598

Designer Topological Insulators in Superlattices

Xiao Li·Fan Zhang·Qian Niu·Ji Feng
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Abstract

Gapless Dirac surface states are protected at the interface of topological and normal band insulators. In a binary superlattice bearing such interfaces, we establish that valley-dependent dimerization of symmetry-unrelated Dirac surface states can be exploited to induce topological quantum phase transitions. This mechanism leads to a rich phase diagram that allows us to design strong, weak, and crystalline topological insulators. Our ab initio simulations further demonstrate this mechanism in [111] and [110] superlattices of calcium and tin tellurides.

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Xiao Li, Fan Zhang, Qian Niu, Ji Feng. 2013-10-24. Designer Topological Insulators in Superlattices. https://doi.org/10.1038/srep06397

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