Josephson spin-current in superconductor-ferromagnetic-superconductor junctions with singlet superconducting leads

Abstract

We study numerically the electronic heat capacity, spin and charge current in a diffusive Superconductor-Ferromagnetic-Superconductor systems، with singlet superconducting leads and non-uniform ferromagnetic layer. Specially, we focus on ferromagnetic layer with domain wall and conical structures incorporation the spin-active interfaces. We investigate, how the 0-π transition is influenced by non-uniform magnetization texture and also the appearance of spin-current in such structures. We find that for ferromagnetic layer with domain wall structure, only the one component of spin-current is non-zero and for conical structure, three components of spin-current are non-zero. Also we find that specific heat of such junctions can be tuned by changing the superconducting phase difference. Interestingly, spin-current shows a discontinuous jump at the 0-π transition points of the critical charge current.

Keywords

• Josephson spin current
• ferromagnetic
• singlet superconductor
• electronic specific heat