Non-Abelian order in s-wave superconductors: Phases and quantum transitions

ORAL

Abstract

Non-Abelian topological superconductivity has been predicted to occur in s-wave superconductors with a sizable spin-orbit (SO) coupling. As is now well known, such a system can be used for topological quantum computation. When an external Zeeman splitting crosses a critical value, the system passes from a regular, non-topological, superconducting phase to a topological one. On the other hand, in the absence of SO coupling this critical value corresponds to the Zeeman splitting above which the system loses its s-wave superconductivity. We are thus led to the paradoxical conclusion that the topological superconducting phase appears in a parameter regime at which the system actually is non- superconducting in the absence of SO coupling. In this work we resolve this paradox.

*Work supported by DARPA-MTO Grant No: FA 9550-10-1-0497, DARPA QuEST, and JQI-NSF-PFC.

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Authors

  • Sumanta Tewari

    • Physics \& Astronomy, Clemson University, Clemson, SC
    • Dept of Physics, Clemson Unversity, South Carolina

  • Tudor Stanescu

    • Department of Physics, West Virginia University, Morgantown, WV

  • Jay Sau

    • Condensed Matter Theory Center, Dept. of Physics, University of Maryland, College Park, MD
    • CMTC, Dept of Physics, University of Maryland, College Park

  • Parag Ghosh

    • Dept. of Physics and Astronomy, George Mason University, Fairfax, VA

  • Sankar Das Sarma

    • Condensed Matter Theory Center, Department of Physics, University of Maryland, College Park, MD 20742
    • Condensed Matter Theory Center, Department of Physics, University of Maryland
    • Univ of Maryland-College Park
    • Condensed Matter Theory Center, Dept. of Physics, University of Maryland, College Park, MD
    • CMTC, Dept of Physics, University of Maryland, College Park
    • Condensed Matter Theory Center, Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA
    • Condensed Matter Theory Center, University of Maryland, College Park
    • Dep. of Physics, Condensed Matter Theory Center, University of Maryland, College Park, Maryland
    • University of Maryland
    • JQI and CMTC, University of Maryland
    • Joint Quantum Institute and Condensed Matter Theory Center, University of Maryland