Vortex states in superconductors with strong Pauli-paramagnetic effect

TL;DR

This paper investigates vortex structures in strong-paramagnetic superconductors using quasiclassical theory, revealing how paramagnetic moments influence various physical properties and explaining experimental observations in CeCoIn_5.

Contribution

It provides a quantitative analysis of paramagnetic effects on vortex states, linking theoretical predictions to experimental data in strongly Pauli-paramagnetic superconductors.

Findings

Paramagnetic moments accumulate around vortex cores.

The H-dependence of specific heat, Knight shift, and magnetization is significantly affected by paramagnetism.

The anomalous FLL form factor in CeCoIn_5 is explained by large paramagnetic contributions.

Abstract

Using the quasiclassical theory, we analyze the vortex structure of strong-paramagnetic superconductors.There, induced paramagnetic moments are accumulated exclusively around the vortex core. We quantitatively evaluate the significant paramagnetic effect in the H-dependence of various quantities, such as low temperature specific heat, Knight shift, magnetization and the flux line lattice (FLL) form factor. The anomalous H-dependence of the FLL form factor observed by the small angle neutron scattering in CeCoIn_5 is attributable to the large paramagnetic contribution.