Pressure-driven tunable properties of the small-gap chalcopyrite topological quantum material ZnGeSb2: A first-principles study

Search for new topological quantum materials is the demand for substantial growth in matter's topological phase. In this search process, theoretical prediction and the obvious experimental verification are crucial. The divination of topological properties in well-known narrow-gap semiconductors is flourishing in quantum material science. We revisited the semiconductor compound in the chalcopyrite series, some of which were potential topological materials. Using this density functional theory-based first-principles calculations, we report a strong topologically nontrivial phase in chalcopyrite ZnGeSb 2, which can act as a model system of strained HgTe. The estimates reveal the non-zero topological invariant (Z 2 ) Dirac cone crossing in the surface spectral functions with spin-momentum locked spin texture. We also report the tunable topological properties from nontrivial to trivial phases under moderate hydrostatic pressure within ≈7 GPa. A minor modification of a lattice parameter is enough to achieve this topological phase transition easily accomplished in an experimental lab. We have incorporated the discontinuity in the tetragonal distortion of non-centrosymmetric ZnGeSb 2 to drive the topological quantum phase transition.