Microstructure and magnetotransport properties of Cu doped Fe 3O4 films

Abstract

A systematic and study on the microstructure and magnetotransport properties of Cu doped Fe3 O4 films prepared by cosputtering is presented. Structural investigations reveal that the Cu doped films are polycrystalline in nature with a preferred growth direction and retain the cubic spinel structure of Fe3 O4. Another characteristic feature of the Cu doped films is the transport mechanism being dominated by spin dependent tunneling across grain boundaries. The magnetic properties of the doped films are markedly sensitive to the doping concentration, with both saturation magnetization and coercivity increasing with increasing Cu doping concentration. In-plane magnetoresistance (MR) measurements show a reduction in MR ratio as the Cu doping concentration is increased. © 2008 American Institute of Physics.