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arXiv · 1706.03970

Topological Phase Transition in Layered XIn$_2$P$_2$ (X = Ca, Sr)

Zhenwei Wang·Guangtao Wang·Xianbiao Shi·Dongyang Wang·Xin Tian
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Abstract

Based on fully relativistic first-principles calculations, we studied the topological properties of layered XIn$_2$P$_2$ (X = Ca, Sr). Band inversion can be induced by strain without SOC, forming one nodal ring in the k$_z$ = 0 plane, which is protected by the coexistence of time-reversal and mirror-reflection symmetry. Including SOC, a substantial band gap is opened along the nodal line and the line-node semimetal would evolve into a topological insulator. These results reveal a category of materials showing quantum phase transition from trivial semiconductor and topologically nontrivial insulator by the tuneable elastic strain engineering. Our investigations provide a new perspective about the formation of topological line-node semimetal under stain.

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Zhenwei Wang, Guangtao Wang, Xianbiao Shi, Dongyang Wang, Xin Tian. 2017-06-13. Topological Phase Transition in Layered XIn$_2$P$_2$ (X = Ca, Sr). https://doi.org/10.1088/1361-6463%2Faa8eaf

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