Time-reversal symmetry breaking state in dirty three-band superconductor

TL;DR

This paper investigates how disorder affects a three-band superconductor with potential for time-reversal symmetry breaking, showing that such states can persist despite impurities, making them experimentally observable.

Contribution

It demonstrates that TRSB states in a three-band superconductor remain stable under moderate disorder, expanding understanding of their robustness and experimental relevance.

Findings

TRSB states survive impurity scattering

Critical temperature is suppressed by disorder

TRSB states are accessible in real materials like iron pnictides

Abstract

I study the effects of disorder on the superconductivity of a three-band model with repulsive interband pairing. Such a model can support several possible superconducting order parameters, including a complex time-reversal symmetry breaking (TRSB) state. Impurity scattering suppresses the critical temperature of all these states, but the complex state survives, and remains a part of the phase diagram of the model even in the presence of moderate amount of disorder. This means that the TRSB states could be experimentally accessible in multiband materials like iron pnictides and chalcogenides.