Magnetic interaction in Co-doped SnO(2) nano-crystal powders.

ABSTRACT

Rutile-type Co-doped SnO(2) nano-crystal powders are prepared by the wet chemical method. The magnetic moment is found to decrease with increasing Co content. There is hysteresis between field cooled (FC) and zero field cooled (ZFC) magnetization when the temperature is below 70 K. These magnetic behaviours represent antiferromagnetic interaction between Co ions. By measuring the magnetization as a function of temperature, the magnetic interaction between Co ions is evaluated qualitatively using the Curie-Weiss law. The value of the effective exchange integral J(1)/k(B) is about -62 K, indicating a very strong antiferromagnetic superexchange interaction between Co ions.