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arXiv · 2201.02347

Pressure driven topological phase transition in chalcopyrite ZnGeSb$_2$

Surasree Sadhukhan·Banasree Sadhukhan·Sudipta Kanungo
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Abstract

Recently topologically non-trivial phases have been identified in few time-reversal invariant systems that lack of inversion symmetry. Using density functional theory based first-principles calculations, we report a strong topologically non-trivial phase in chalchopyrite ZnGeSb$_2$, which can act as a model system of strained HgTe. The calculations reveal the non-zero topological invariant ($Z_2$), the presence of Dirac cone crossing in the surface spectral functions with spin-momentum locking. We also show that the application of moderate hydrostatic pressure ($\sim$7 GPa) induces topological phase transition from topological non-trivial phase to a topologically trivial phase. A discontinuity in the tetragonal distortion of non-centrosymmetric ZnGeSb$_2$ plays a crucial role in driving this topological phase transition.

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Surasree Sadhukhan, Banasree Sadhukhan, Sudipta Kanungo. 2022-01-07. Pressure driven topological phase transition in chalcopyrite ZnGeSb$_2$. https://arxiv.org/abs/2201.02347

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