We study the dc Josephson effect in a diffusive multilayered SF'FF'S structure, where S is a superconductor and F,F' are different ferromagnets. We assume that the exchange energies in the F' and F layers are different ($% h $ and $H$, respectively) and the middle F layer consists of two layers with parallel or antiparallel magnetization vectors $M$. The $M$ vectors in the left and right F' layers are generally not collinear to those in the F layer. In the limit of a weak proximity effect we use a linearized Usadel equation. Solving this equation, we calculate the Josephson critical current for arbitrary temperatures, arbitrary thicknesses of the F' and F layers ($% L_{ h}$ and $L_{ H}$) in the case of parallel and antiparallel $M$ orientations in the F layer. The part of the critical current $I_{ cSR}$ formed by the short-range (SRC) singlet and S=0 triplet condensate components decays on a short length $\xi_{ H}=\sqrt{ D/H}$, whereas the part $% I_{ cLR}$ due to the long-range triplet $|S|=1$ component (LRTC) decreases with increasing $L_{ H}$ on the length $\xi_{ N}=\sqrt{ D/\pi T}$. Our results are in agreement with the experiment \cite{ Birge}.
Categories: cond-mat.supr-con