Synthesis and magnetic behavior of nanostructured ferrites for spintronics

Zinc oxide based material systems are considered as promising candidate for spintronic devices if it could be coupled in heterostructure with a suitable ferromagnetic material. We synthesized Zn, Mn and Co substituted iron oxide powders and thin films using solution-based approaches. Structural properties of these materials were studied by X-ray diffraction, FT-IR and closed cycle SQUID for magnetic characterization. These studies indicates that Zn1−xCoxFe2O4, Mn0.5Zn0.5Fe2O4 and CoFe2O4 exhibited ferrimagnetic and superparamagnetic behavior, respectively, at room temperature. Superparamagnetic behavior in Mn0.5Zn0.5Fe2O4 and CoFe2O4 is attributed to the extremely small crystal size.