Optical properties of (Ga _1-xMn _x)N thin films with a low Mn concentration grown on GaN buffer layers

The optical properties of (Ga _1-xMn _x)N thin films with a low Mn concentration grown on GaN buffers by using molecular beam epitaxy were investigated. The magnetization curve as a function of magnetic field at 5 K indicated that ferromagnetism existed in the (Ga _1-xMn _x)N thin films, and the magnetization curve as a function of temperature showed that the Curie temperature (T _c) of the (Ga _1-xMn _x)N thin film was above room temperature. Photoluminescence spectra measured at several temperatures showed band-edge exciton transitions in (Ga _1-xMn _x)N thin films with diluted magnetic semiconductor properties and a T _c value above room temperature, indicative of the Mn atoms acting as substitution. These results indicate that (Ga _1-xMn _x)N thin films hold promise for potential applications in spintronic devices in the blue region of the spectrum.