Peculiarities of performance of the spin valve for the superconducting curren

The spin valve effect for the superconducting current based on the superconductor/ferromagnet proximity effect has been studied for a CoO$_x$/Fe1/Cu/Fe2/Cu/Pb multilayer. {The magnitude of the effect $\Delta T_c =T_c^{\text{AP}} -T_c^{\text{P}}$, where $T_c^{\text{P}}$ and $T_c^{\text{AP}}$ are the superconducting transition temperatures for the parallel (P) and antiparallel (AP) orientation of magnetizations, respectively, has been measured for different thicknesses of the Fe1 layer $d_{\text{Fe1}}$. The obtained dependence of the effect on $d_{\text{Fe1}}$ reveals that $\Delta T_c$} can be increased in comparison with the case of a half-infinite Fe1 layer considered by the previous theory. A maximum of the spin valve effect occurs at $d_{\text{Fe1}}\sim d_{\text{Fe2}}$. At the optimal value of $d_{\text{Fe1}}$ almost full switching from the normal to the superconducting state when changing the mutual orientation of magnetizations of the iron layers Fe1 and Fe2 from P to AP is demonstrated.