Antiferromagnetic coupling in a macroscopic ferrimagnet EuS-Co

Antiferromagnetic coupling between nanoparticles of EuS and Co matrix, both ferromagnetically ordered, has been observed in the mechanically alloyed nanocomposite (EuS)/sub 30/Co/sub 70/ below the Curie temperature of EuS. The coupling strength was found to increase with decreasing particle size of EuS. This was attributed to the increased presence of EuS in the proximity of the interface between EuS and Co that may strongly influence the short range exchange coupling.