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arXiv · 1606.06227

Strain in Epitaxial High-Index Bi2Se3(221) Films Grown by Molecular-Beam Epitaxy

B. Li·W. G. Chen·X. Guo·W. K. Ho·X. Q. Dai·J. F. Jia·M. H. Xie
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Abstract

High-index Bi2Se3(221) film has been grown on In2Se3-buffered GaAs(001), in which a much retarded strain relaxation dynamics is recorded. The slow strain-relaxation process of in epitaxial Bi2Se3(221) can be attributed to the layered structure of Bi2Se3 crystal, where the epifilm grown along [221] is like a pile of weakly-coupled quintuple layer slabs stacked side-by-side on substrate. Finally, we have revealed the strong chemical bonding at the interface of Bi2Se3 and In2Se3 by plotting differential charge contour calculated by first-principle method. This study points to the feasibility of achieving strained TIs for manipulating the properties of topological systems.

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B. Li, W. G. Chen, X. Guo, W. K. Ho, X. Q. Dai, J. F. Jia, M. H. Xie. 2016-09-14. Strain in Epitaxial High-Index Bi2Se3(221) Films Grown by Molecular-Beam Epitaxy. https://doi.org/10.1016/j.apsusc.2016.11.189

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