Josephson effect in a singlet superconductor-ferromagnet-triplet superconductor junction

Abstract

We study the current-phase relation of a ballistic SIFIT junction, consisting of a spin-singlet superconductor (S), an insulating ferromagnetic interface (I), a weak ferromagnetic metal (F), another insulating ferromagnetic interface (I), and a spin-triplet superconductor (T). We use the generalized quasiclassical formalism developed by Millis et al. to compute the current density and the free energy of the junction for arbitrary orientations of the magnetizations of the junction barrier. We investigate in detail the effect of the distribution of magnetization on the various harmonics of the current-phase relation and the transition of the ground state of the junction. A magnetization parallel to the d-vector of the triplet superconductor can lead to an anomalous Josephson current and a transition of the ground state from the π/2-state to the 3π/2-state. The .-state junction can be realized for a noncollinear orientation of the barrier magnetizations in the plane perpendicular to the d-vector.