Josephson coupling through ferromagnetic bilayer with non-collinear magnetizations

Abstract

We study the Josephson effect in clean heterojunctions consisting of ferromagnetic bilayer between superconductors. We solve the scattering problem based on the Bogoliubov-de Gennes equation for any relative orientation of in-plane magnetizations, arbitrary transparency of interfaces, and mismatch of Fermi wave vectors. Both spin singlet and triplet superconducting correlations are taken into account, and the Josephson current is calculated as a function of the ferromagnetic layers thicknesses and of the angle α between their magnetizations. Dramatic impact of spin triplet superconducting correlations on the Josephson effect is not found in the clean limit. © 2007 American Institute of Physics.