Ferromagnetic semiconductor nanoclusters: Co-doped Cu2O

Abstract

5% Co-doped cuprous oxide dilute magnetic semiconducting cluster film composed of two different sizes of crystalline nanoclusters, prepared using sputtering-aggregation technique is found to be ferromagnetic at 400K. With the increase in average crystallite size from 4.2to8nm, the coercivity increased. Magnetic field up to 2T is applied and saturation magnetization is achieved at 3kOe field in both cases. Cu2O phase is observed from cluster film deposited on Si wafer when analyzed using x-ray diffraction. Co in Cu2O host reveals a +2 oxidation state via x-ray photoelectron spectroscopy. Positive magnetoresistance from samples exhibits a temperature dependent decrease.