The disordered Fulde-Ferrel-Larkin-Ovchinnikov state in d-wave superconductors

Abstract

We study the Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) superconducting state in disordered systems. We analyze the microscopic model, in which the d-wave superconductivity is stabilized near the antiferromagnetic quantum critical point, and investigate two kinds of disorder, namely, box disorder and point disorder, on the basis of the Bogoliubov-de Gennes (BdG) equation. The spatial structure of the modulated superconducting order parameter and the magnetic properties in the disordered FFLO state are investigated. We point out the possibility of the 'FFLO glass' state in the presence of strong point disorders, which arises from the configurational degree of freedom of the FFLO nodal plane. The distribution function of the local spin susceptibility is calculated and its relationship with the FFLO nodal plane is clarified. We discuss the nuclear magnetic resonance (NMR) measurements for CeCoIn5. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.