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arXiv · 1105.5841

Strain driven onset of non-trivial topological insulating states in Zintl Sr$_2X$ compounds ($X$=Pb, Sn)

Yan Sun·Xing-Qiu Chen·Dianzhong Li·Cesare Franchini·Seiji Yunoki·Yiyi Li·Zhong Fang
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Abstract

We explore the topological behavior of the binary Zintl phase of the alkaline earth metals based compounds Sr$_2$Pb and Sr$_2$Sn using both standard and hybrid density functional theory. It is found that Sr$_2$Pb lies on the verge of a topological instability which can be suitably tuned through the application of a small uniaxial expansion strain ($>$ 3%). The resulting non-trivial topologically insulating state display well-defined metallic states in the Sr$_{2}$Pb(010) surface, whose evolution is studied as a function of the film thickness.

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Yan Sun, Xing-Qiu Chen, Dianzhong Li, Cesare Franchini, Seiji Yunoki, Yiyi Li, Zhong Fang. 2011-05-30. Strain driven onset of non-trivial topological insulating states in Zintl Sr$_2X$ compounds ($X$=Pb, Sn). https://doi.org/10.1103/physrevb.84.165127

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