Double band inversion in the topological phase transition of Ge1-xSnx alloys

Abstract

We use first-principles simulation and virtual crystal approximation to reveal the unique double band inversion and topological phase transition in Ge1-xSnx alloys. Wavefunction parity, spatial charge distribution and surface state spectrum analyses suggest that the band inversion in Ge1-xSnx is relayed by its first valence band. As the system evolves from Ge to α-Sn, its conduction band moves down, and inverts with the first and the second valence bands consecutively. The first band inversion makes the system nontrivial, while the second one does not change the topological invariant of the system. Both the band inversions yield surface modes spanning the individual inverted gaps, but only the surface mode in the upper gap associates with the nontrivial nature of tensile-strained α-Sn.

arXiv comment5 pages, 6 figures

References in corpus (12)

• Topological Insulators
• Relativistic separable dual-space Gaussian Pseudopotentials from H to Rn
• Topological Insulators with Inversion Symmetry
• Discovery of a Three-dimensional Topological Dirac Semimetal, Na3Bi
• Colloquium: Topological Band Theory
• First direct observation of Spin-textures in Topological Insulators : Spin-resolved ARPES as a probe of topological quantum spin Hall effect and Berry's phase
• Zoo of quantum-topological phases of matter
• Symmetry Protected Topological phases of Quantum Matter
• Elemental Topological Insulator with a Tunable Fermi Level: Strained α-Sn on InSb(001)
• Spin Polarization of Gapped Dirac Surface States Near the Topological Phase Transition in TlBi(S1-xSex)2
• Ab initio study of InxGa(1-x)N - performance of the alchemical mixing approximation
• Anomalous behavior of the electronic structure of (Bi${}_{1-x}$In${}_x$)${}_2$Se${}_3$ across the quantum-phase transition from topological to trivial insulator

Cited by in corpus (1)

• Topological electronic structure of YbMg${}_2$Bi${}_2$ and CaMg${}_2$Bi${}_2$