Coexistence of Ferromagnetism and Superconductivity in Noncentrosymmetric Materials with Cubic Symmetry

TL;DR

This study models how noncentrosymmetric cubic materials can host coexistence of ferromagnetism and superconductivity, revealing helical magnetic phases and modulated superconducting order parameters influenced by magnetic structures.

Contribution

It introduces a Ginzburg-Landau framework to analyze the interplay of ferromagnetism and superconductivity in noncentrosymmetric cubic materials, highlighting the emergence of helical magnetic phases and order parameter modulations.

Findings

Helical magnetic phases are induced by noncentrosymmetricity.

Long-wavelength magnetic order causes superconducting order parameter modulations.

Superconductivity is suppressed at magnetic domain walls.

Abstract

This is a model study for the emergence of superconductivity in ferromagnetically ordered phases of cubic materials whose crystal structure lacks inversion symmetry. A Ginzburg-Landau-type theory is used to find the ferromagnetic state and to determine the coupling of magnetic order to superconductivity. It is found that noncentrosymmetricity evokes a helical magnetic phase. If the wavelength of the magnetic order is long enough, it gives rise to modulations of the order parameter of superconductivity, both in modulus and complex phase. At magnetic domain walls the nucleation of superconductivity is found to be suppressed as compared to the interior of ferromagnetic domains.