Magnetic properties in rare-earth substituted spinel Co0.2Zn0.8Fe2-xRExO4 (RE=Dy, Ho and Er, x=0.05)

We report the magnetic properties of rare earth (Dy, Ho and Er) substituted Co0.2Zn0.8Fe2-xRExO4 spinel oxide. This is atypical spinel oxide material where frustration and exchange couplings between 3d and 4f electrons spin play a major role in magnetic ordering. The low field dc magnetization and ac susceptibility data show that the system goes from paramagnetic to ferromagnetic cluster glass phase and then to spin glass like phase at a low temperature. The. data suggest the evidence for the existence of super ferromagnetic clusters at approximate to 170 K The aim of the present work is to stabilize the system and search for RE based re-entrant spin glass like phase, as considerable work has been reported in transition metal based system. (C) 2001 Elsevier Science B.V. All rights reserved.