Non-Trivial Topological Phase in the Sn_{1-x}In_xTe Superconductor

Abstract

Whereas SnTe is a inverted band gap topological crystalline insulator, the topological phase of the alloy Sn_{1-x}In_xTe, a topological superconductor candidate, has not been clearly studied so far. Our calculations show that the Sn_{1-x}In_xTe band gap reduces by increasing the In content, becoming a metal for x>0.1. However, the band inversion at the fcc L point for both gapped and gapless phases has been maintained. Furthermore, the computed topological invariant shows a non-trivial phase with a mirror Chern number n_M = -2 for In concentrations of x=0.03125, x=0.125, and x=0.25. We also identify pairs of topologically protected states on the (001) surface of Sn_{1-x}In_xTe with +/- i mirror eigenvalues. The character of these topological states is affected by In dopant. As the In content x increases, the Dirac crossing point moves further away from the L point, and the Fermi velocity of the topological states increases significantly. Our results demonstrate a non-trivial topological phase for the superconductor Sn_{1-x}In_xTe, and provide a detailed description of the topological state properties.

References in corpus (19)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Topological Crystalline Insulators
• Computing topological invariants without inversion symmetry
• Z2Pack: Numerical Implementation of Hybrid Wannier Centers for Identifying Topological Materials
• Bulk superconducting phase with a full energy gap in the doped topological insulator Cu_xBi_2Se_3
• Momentum space imaging of Cooper pairing in a half-Dirac-gas topological superconductor (a helical 2D topological superconductor)
• Electrochemical synthesis and superconducting phase diagram of Cu_xBi2Se3
• Enhanced superconducting pairing interaction in indium-doped tin telluride
• Superconducting properties of the In substituted Topological Crystalline Insulator, SnTe
• Superconductivity in Tl_{0.6}Bi_{2}Te_{3} Derived from a Topological Insulator
• Evidence of nodes in the order parameter of the superconducting doped topological insulator Nb${}_x$Bi${}_2$Se${}_3$ via penetration depth measurements
• Resonance-state-induced superconductivity at high Indium contents in In-doped SnTe
• Revealing surface states in In-doped SnTe superconducting nanoplates with low bulk mobility
• Studies of the superconducting properties of Sn1-xInxTe (x=0.38 to 0.45) using muon-spin spectroscopy
• Superconductivity, pairing symmetry, and disorder in the doped topological insulator Sn${}_{1-x}$In${}_x$Te for x $\ge$ 0.10
• Electron and hole contributions to normal-state transport in the superconducting system Sn${}_{1-x}$In${}_x$Te
• Spin-singlet superconductivity in doped topological crystalline insulator Sn_{0.96}In_{0.04}Te
• Topological Nonsymmorphic Ribbons out of Symmorphic Bulk
• Unusual phonon density of states and response to the superconducting transition in the In-doped topological crystalline insulator Pb${}_{0.5}$Sn${}_{0.5}$Te