Fractional flux quanta at intrinsic metallic interfaces of noncentrosymmetric superconductors

TL;DR

This paper explores how intrinsic interfaces in noncentrosymmetric superconductors can host fractional flux quanta due to parity-mixed pairing and time-reversal symmetry breaking, impacting flux dynamics.

Contribution

It introduces the concept of fractional flux quanta at intrinsic interfaces of noncentrosymmetric superconductors with spin-orbit coupling.

Findings

Fractional flux quanta can form at interfaces due to parity-mixed pairing.

Time-reversal symmetry breaking enables unique flux line configurations.

Implications for flux creep behavior in these materials.

Abstract

We examine intrinsic interfaces separating crystalline twin domains of opposite spin-orbit coupling in a noncentrosymmetric superconductor such as CePt3Si. At these interfaces, low-energy Andreev bound states occur as a consequence of parity-mixed Cooper pairing, and a superconducting phase which violates time reversal symmetry can be realized. This provides an environment allowing flux lines with fractional flux quanta to be formed at the interface. Their presence could have strong implications on the flux creep behavior in such superconductors.