Transition in a magnetic non-collinear spin-flop state in a Fe/Pd/Gd/Pd superlattice

The influence of a Pd spacer on the magnetic properties of Gd/Fe heterostructures has been studied. We have prepared using ultrahigh vacuum sputtering multilayered [Fe(3.5 nm)/Pd(1.2 nm)/Gd(5.0 nm)/Pd(1.2 nm)]$_{12}$ structure. By using Polarized Neutron Reflectometry at temperature of 10 K we have observed strong increase in the intensity of neutron spin-flip scattering above magnetic field of 1.5 kOe. Combined analysis of magnetometry and polarized neutron reflectometry data allowed us to find out that the observed increase in spin-flip scattering is related to the spin-flop transition. Although the spin-flop transition were already seen in Fe/Gd systems, the use of Pd in our case allowed the suppression of the magnetic field of the transition making thus possible the use of Fe/Pd/Gd systems for diverse spintronic applications.