  Structural, magnetic, and superconducting properties of S/F bilayers
Nb/Cu40Ni60 deposited on silicon substrate have been characterized using
Polarized Neutron Reflectometry and complementary techniques. The study allowed
to determine real thicknesses of the S and F layers as well as the r.m.s.
roughness of the S/F interfaces. The latter does not exceed 1 nm, showing the
high quality of the S/F interface. Using SQUID and a mutual inductance setup we
determined the superconducting transition temperatures of the samples, which
are in agreement with the literature data. Using of PNR for the single S layer
allowed to determine the screening length lambda of the superconducting layer,
lambda = 120 nm. This value is higher than the London penetration depth for
pure niobium which may indicate that the superconductor is in the dirty limit.
PNR and SQUID studies of magnetic properties of the CuNi layer have shown the
presence of ferromagnetism in all investigated samples.
