Diamagnetic critical singularity in unconventional ferromagnetic superconductors

TL;DR

This paper investigates the critical behavior of diamagnetic properties near the phase transition in unconventional ferromagnetic superconductors with p-wave pairing, highlighting the suppression of observable singularities under pressure variations.

Contribution

It provides a theoretical analysis of diamagnetic singularities in ferromagnetic superconductors, including crossover behavior in different dimensions, within a Gaussian approximation.

Findings

Diamagnetic singularities are suppressed at large pressure variations.

Crossover from weak to strong magnetic induction is characterized.

Results are applicable to both quasi-2D and 3D superconductors.

Abstract

The scaling properties of the free energy, the diamagnetic moment, and the diamagnetic susceptibility above the phase transition from the ferromagnetic phase to the phase of coexistence of ferromagnetic order and superconductivity in unconventional ferromagnetic superconductors with spin-triplet (p-wave) electron paring are considered. The crossover from weak to strong magnetic induction is described for both quasi-2D (thin films) and 3D (bulk) superconductors. The singularities of diamagnetic moment and diamagnetic susceptibility are dumped for large variations of the pressure and, hence, such singularities could hardly be observed in experiments. The results are obtained within Gaussian approximation on the basis of general theory of ferromagnetic superconductors with p-wave electron pairing.