Onset of long-range ferromagnetic order in a system of ferromagnetic particles with giant magnetic moments

Abstract

Magnetic, x-ray, and small-angle neutron scattering data obtained for the decomposed alloy Cu64Mn9Al27 are used to show that the onset of long-range ferromagnetic order in a system of small superparamagnetic grains dissolved in a nonmagnetic matrix is attributable to cooperative ordering of their magnetic moments.