Non-monotonic behaviour of the superconducting order parameter in   Nb/PdNi bilayers observed through point contact spectroscopy
  Point contact spectroscopy measurements have been performed on Nb/PdNi bilayers in which the thickness of the Nb layer, dNb, was kept constant to 40 nm while the thickness of PdNi, dPdNi, was changed from 2 nm to 9 nm. Features related to the superconducting gap induced in the ferromagnet have been observed in the dV/dI versus V curves. These structures show a non-monotonic behaviour as a function of dPdNi as a consequence of the damped oscillatory behaviour of the superconducting order parameter in the ferromagnetic layer. 
P. Romano, A. Polcari, C. Cirillo, and C. Attanasio
cond-mat.supr-con