Work

Unconventional Superconductivity on a Topological Insulator

Year: 2010

Type: article

Abstract: We study proximity-induced superconductivity on the surface of a topological insulator (TI), focusing on unconventional pairing. We find that the excitation spectrum becomes gapless for any spin-triplet pairing, such that both subgap bound states and Andreev reflection is strongly suppressed. For spin-singlet pairing, the zero-energy surface state in the d(xy)-wave case becomes a Majorana fermion, in contrast with the situation realized in the topologically trivial high-T(c) cuprates. We also study the influence of a Zeeman field on the surface states. Both the magnitude and direction of this field are shown to strongly influence the transport properties, in contrast with the case without TI. We predict an experimental signature of the Majorana states via conductance spectroscopy.

Source: Physical Review Letters

DOI: 10.1103/physrevlett.104.067001

Authors: Jacob Linder, Yukio Tanaka, Takehito Yokoyama, Asle Sudbø, Naoto Nagaosa

Institutions: Norwegian University of Science and Technology, Nagoya University, The University of Tokyo, RIKEN, RIKEN Advanced Science Institute

Language: English

Topic: Topological Materials and Phenomena

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Norges Forskningsråd, Japan Society for the Promotion of Science

Award: G2286976256