Time-reversal symmetry breaking in superconductors through loop pair-current order

ORAL

Abstract

We propose a superconducting instability where microscopic loop pair-currents form spontaneously within a unit cell at the critical temperature, Tc . Such currents break time-reversal symmetry (TRS) without needing an unconventional pairing mechanism. Using Ginzburg-Landau theory
we show how they emerge in a toy model and estimate an upper bound for the resulting magnetisation, which is consistent with recent muon-spin relaxation experiments. We discuss the crystal symmetry requirements and show that they are met by the Re6X (X=Zr, Hf, Ti) family of TRS-breaking, but otherwise seemingly conventional, superconductors.

Presenters

  • Sudeep Ghosh

    School of Physical Sceinces, University of Kent, Canterbury, UK, Physics, University of Kent

Authors

  • Sudeep Ghosh

    School of Physical Sceinces, University of Kent, Canterbury, UK, Physics, University of Kent

  • Jorge Quintanilla

    SPS, University of Kent, School of Physical Sceinces, University of Kent, Canterbury, UK, Physics, University of Kent, University of Kent

  • James Annett

    H. H. Wills Physics Laboratory, University of Bristol, Bristol, UK, Physics, University of Bristol