Magnetism in transition-metal-doped In2O3 thin films

Laser ablated transition-metal (TM)-doped In2O3 thin films grown under appropriate conditions on both MgO and Al2O3 substrates can be well crystallized and ferromagnetic at room temperature. Of all the dopants, Ni seems to be the most promising candidate since doping Ni in In2O3 results in semiconducting films with the largest magnetic moment. Films are cluster-free. Magnetic force microscopy measurements confirm that the magnetic signals at room temperature are real. Moreover, compared to TM:In2O3 films deposited on MgO, films on Al2O3 have smaller grains and those are better connected, so that the film texture is smoother and the magnetic domains are more uniform. The size of ferromagnetic domains is determined to be about 1 mu m. The room temperature ferromagnetism in V/Cr/Fe/Co/Ni-doped In2O3 films probably originates from the doped In2O3 matrices.