Superconductor–ferromagnet bi-layers: a comparison of s-wave and d-wave orderparameters

Abstract

We study superconductor–ferromagnet bi-layers, not only for s-wave, but also for d-wavesuperconductors. We observe oscillations of the critical temperature when varying thethickness of the ferromagnetic layer for both s-wave and d-wave superconductors. However,for a rotated d-wave order parameter the critical temperature differs considerably from thatfor the unrotated case. In addition we calculate the density of states for differentthicknesses of the ferromagnetic layer; the results reflect the oscillatory behaviour of thesuperconducting correlations.