Different types of the Fulde-Ferrell-Larkin-Ovchinnikov states induced by anisotropy effects

TL;DR

This paper explores how anisotropy effects influence the formation and transition of various Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) states in superconductors, emphasizing the role of crystal structure and magnetic field orientation.

Contribution

It demonstrates, using a phenomenological approach, that crystal anisotropy critically determines the structure and transitions of FFLO states in magnetic fields.

Findings

Different FFLO states can be induced by anisotropy effects.

Transitions between FFLO states occur with temperature changes or magnetic field rotation.

FFLO modulation can manifest as higher Landau level states or along the magnetic field.

Abstract

The crystal structure determines both the Fermi surface and pairing symmetry of the superconducting metals. It is demonstrated in the framework of the general phenomenological approach that this is of the primary importance for the determination of the structure of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase in the magnetic field. The FFLO modulation of the superconducting order parameter may be revealed in the form of the higher Landau level states or/and modulation along the magnetic field. The transition between different FFLO states could occur with the temperature variation or with the magnetic field rotation.