Effect of the variation of the exchange energy on the superconducting critical temperature of S/F/S trilayers.

The effect of the exchange energy variation in weakly ferromagnetic alloys on the superconducting resistive transition of superconductor/ferromagnet/superconductor (S/F/S) trilayers is studied. Critical temperature, T, and resistive transitions versus the F-layer thickness, d, have been analyzed in Nb/CuNi/Nb and Nb/PdNi/Nb trilayers. We show that T( d) dependence is sensitive to magnetic inhomogeneities in the F-layer for values of d corresponding to thickness range where the π-superconducting state is established. [ABSTRACT FROM AUTHOR]