Nonmonotonic critical temperature in ferromagnet/superconductor/ferromagnet trilayers

Abstract

We show the equivalence between the Usadel equations and the Takahashi and Tachiki theory. The method for solving the problem of superconductor (S)/ferromagnet (F) proximity systems in the multimode method is proposed. The critical temperature Tc of FSF trilayers reveals the nonmonotonic dependence on the F thickness df. An investigation of Tc, using our approach, as a function of material parameters as well as the mutual orientation of ferromagnetic moments provides various types of T c(df) behavior, including the re-entrant behavior. © 2004 Elsevier B.V. All rights reserved.