Effect of Born and unitary impurity scattering on the Kramer-Pesch shrinkage of a vortex core in an s-wave superconductor

TL;DR

This paper theoretically examines how non-magnetic impurities in different scattering regimes affect the temperature-dependent vortex core shrinkage in s-wave superconductors, revealing weaker impurity effects in the unitary limit compared to the Born limit.

Contribution

It compares impurity effects in the Born and unitary limits on vortex core shrinkage using quasiclassical theory, highlighting differences in impurity impact.

Findings

Weaker impurity effect in the unitary limit in the moderately clean regime.

Stronger vortex core shrinkage in the unitary limit than in the Born limit.

Impurity scattering regime influences vortex core behavior.

Abstract

We theoretically investigate a non-magnetic impurity effect on the temperature dependence of the vortex core shrinkage (Kramer-Pesch effect) in a single-band s-wave superconductor. The Born limit and the unitary limit scattering are compared within the framework of the quasiclassical theory of superconductivity. We find that the impurity effect inside a vortex core in the unitary limit is weaker than in the Born one when a system is in the moderately clean regime, which results in a stronger core shrinkage in the unitary limit than in the Born one.