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arXiv · 0908.3654

Oscillatory crossover from two dimensional to three dimensional topological insulators

Chao-Xing Liu·HaiJun Zhang·Binghai Yan·Xiao-Liang Qi·Thomas Frauenheim·Xi Dai·Zhong Fang·Shou-Cheng Zhang
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Abstract

We investigate the crossover regime from three dimensional topological insulators $Bi_2Te_3$ and $Bi_2Se_3$ to two dimensional topological insulators with quantum spin Hall effect when the layer thickness is reduced. Using both analytical models and first-principles calculations, we find that the crossover occurs in an oscillatory fashion as a function of the layer thickness, alternating between topologically trivial and non-trivial two dimensional behavior.

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Chao-Xing Liu, HaiJun Zhang, Binghai Yan, Xiao-Liang Qi, Thomas Frauenheim, Xi Dai, Zhong Fang, Shou-Cheng Zhang. 2009-09-16. Oscillatory crossover from two dimensional to three dimensional topological insulators. https://doi.org/10.1103/physrevb.81.041307

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