Magnetic properties of Pd-2.9 at.t% Fe fine particles

Magnetization and small-angle-polarized neutron-scattering measurements have been performed on Pd-2.9 at. % Fe fine particles prepared by the conventional gas evaporation method. It was found that decreasing the particle size reduces the saturation magnetization at 5 K. This reduction can be explained in terms of a nonmagnetic surface shell whose thickness is estimated to be ∼12 Å in the sample, with a 162-Å median radius based on the small-angle-polarized neutron-scattering experiments. The saturation magnetization of the core is estimated to be enhanced by a factor of 1.3 compared with that of the bulk PdFe. This probably indicates that the Pd host in the PdFe particles is more magnetically enhanced compared with that in the bulk PdFe, which is consistent with our previous report on pure Pd fine particles.