Possible Topological Superconductivity in a Topological Crystalline Insulator (Pb${}_{1-x}$Sn${}_x$)${}_{1-y}$In${}_y$Te

Abstract

Superconductivity in topological insulators is expected to show very unconventional features such as $p+ip$ order parameter, Majorana fermions etc. However, the intrinsic superconductivity has been observed in a very limited number of materials in which the pairing symmetry is still a matter of debate. Here, we study the topological crystalline insulator (Pb${}_{1-x}$Sn${}_x$)${}_{1-y}$In${}_y$Te, where a peculiar insulator to superconductor transition was previously reported near the gap inversion transition, when the system is nearly a 3-dimensional Dirac semimetal. Both the existence of superconductivity near the 3-dimensional Dirac semimetal and the occurrence of insulator to superconductor transition in an isotropic material is highly unusual. We suggest that the observed phenomena are related to an intrinsic instability of a 3-dimensional Dirac semimetal state in (Pb${}_{1-x}$Sn${}_x$)${}_{1-y}$In${}_y$Te and "flattening" of the bulk valence and conduction bands as they acquire a Mexican hat-like dispersion on the inverted side of the phase diagram. This favors the pairing instability if the chemical potential is pinned to these flat regions.

9 pages, 5 figures

References in corpus (25)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• Topological Crystalline Insulators
• Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase
• Classification of stable three-dimensional Dirac semimetals with nontrivial topology
• The Quantum Spin Hall Effect: Theory and Experiment
• Odd-Parity Pairing and Topological Superconductivity in a Strongly Spin-Orbit Coupled Semiconductor
• Proximity-induced high-temperature superconductivity in topological insulators Bi2Se3 and Bi2Te3
• Tuning phase transition between quantum spin Hall and ordinary insulating phases
• Spin-orbit interaction effect in the electronic structure of \BiTe \ observed by angle-resolved photoemission spectroscopy
• Enhanced superconducting pairing interaction in indium-doped tin telluride
• A new superconductor derived from topological insulator heterostructure
• Absence of a Proximity Effect in a Topological Insulator on a Cuprate Superconductor: Bi2Se3/Bi2Sr2CaCu2O8
• Superconductivity induced by In substitution into the topological crystalline insulator Pb(0.5)Sn(0.5)Te
• Giant Photonic Response of Mexican-hat Topological Semiconductors for Mid-infrared to THz Applications
• Indium substitution effect on the topological crystalline insulator family (Pb${}_{1-x}$Sn${}_x$)${}_{1-y}$In${}_y$Te: Topological and superconducting properties
• Inducing Lifshitz transition by extrinsic doping of surface bands in topological crystalline insulator Pb${}_{1-x}$Sn${}_x$Se
• Surface-state-dominated transport in crystals of the topological crystalline insulator In-doped Pb${}_{1-x}$Sn${}_x$Te
• Superconductor--Insulator Transition in a non-Fermi Liquid
• Electron-phonon coupling and superconductivity in the doped topological-crystalline insulator (Pb${}_{0.5}$Sn${}_{0.5}$)${}_{1-x}$In${}_x$Te
• Spin-polarization of topological crystalline and normal insulator Pb${}_{1-x}$Sn${}_x$Se (111) epilayers probed by photoelectron spectroscopy
• Dirac energy spectrum and inverted band gap in metamorphic InAsSb/InSb superlattices
• Origin of Suppression of Proximity Induced Superconductivity in Bi/Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$ Heterostructure

Cited by in corpus (1)

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