Unexpected superconductivity at nanoscale junctions made on the topological crystalline insulator Pb${}_{0.6}$Sn${}_{0.4}$Te

Abstract

Discovery of exotic phases of matter from the topologically non-trivial systems not only makes the research on topological materials more interesting but also enriches our understanding of the fascinating physics of such materials. Pb${}_{0.6}$Sn${}_{0.4}$Te was recently shown to be a topological crystalline insulator. Here we show that by forming a mesoscopic point-contact using a normal non-superconducting elemental metal on the surface of Pb${}_{0.6}$Sn${}_{0.4}$Te a novel superconducting phase is created locally in a confined region under the point-contact. This happens while the bulk of the sample remains to be non-superconducting and the superconducting phase emerges as a nano-droplet under the point-contact. The superconducting phase shows a high transition temperature $T_c$ that varies for different point-contacts and falls in a range between 3.7 K and 6.5 K. Therefore, this Letter presents the discovery of a new superconducting phase on the surface of a topological crystalline insulator and the discovery is expected to shed light on the mechanism of induced superconductivity in topologically non-trivial systems in general.

The submission contains 22 pages including supplementary material. The main text contains 3 figures, 36 references and supplementary material contains 11 figures and one table

References in corpus (9)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Topological Crystalline Insulators
• Introduction to topological superconductivity and Majorana fermions
• Bulk superconducting phase with a full energy gap in the doped topological insulator Cu_xBi_2Se_3
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• Electrochemical synthesis and superconducting phase diagram of Cu_xBi2Se3
• Dirac mass generation from crystal symmetry breaking on the surfaces of topological crystalline insulators
• Enhanced superconducting pairing interaction in indium-doped tin telluride
• Superconducting properties of the In substituted Topological Crystalline Insulator, SnTe

Cited by in corpus (2)

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