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.

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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