Ferromagnetism in Co-doped indium–tin oxide films

Co-doped indium–tin oxide (ITO) films were produced by magnetron sputtering on fused quartz substrates under various conditions. We find that post-growth processing of films affects crucially their electronic and magnetic properties. Films with 30 at% of Co show hysteretic magnetization and anomalous Hall effect up to room temperature. Values of up to 1.6 μB per Co atom are obtained for the saturation magnetic moment in these films. A mixed magnetic state with Co-rich ITO or Co-metal nanoclusters within a homogeneous ITO:Co matrix might give rise to such behavior.