Ferromagnetic behavior in Cr- and Mn-doped indium-tin oxide thin films

High-temperature ferromagnetism is demonstrated in Cr- and Mn-doped indium-tin oxide (ITO) films deposited using reactive thermal evaporation. These films were grown on sapphire (0001), Si/SiO$_2$, as well as Si(001) substrates with the highest magnetic moment observed around $\sim$1$\mu_{B}$/Mn. The electrical conduction is n type, an anomalous Hall effect was observed, showing that the carriers in this system are spin polarized. Mn-doped samples were single-phase, whereas at high Cr concentrations, there was CrO$_2$ present. The carrier concentration can be varied independent of the Mn concentration in this transparent ferromagnetic semiconductor for its easy integration into magneto-optoelectronic devices. Supported by the CMI project at MIT and NSF