Photoluminescence quantum efficiency of Nd optical centers in GaN epilayers

We report the photoluminescence quantum efficiency of Nd optical centers as well as the thermal quenching mechanism in GaN epilayers prepared by plasma-assisted molecular beam epitaxy. High resolution infrared spectroscopy, quantum yield and temperature dependence measurements of photoluminescence intensity from Er ions in GaN under resonant and non-resonant excitations were performed. The data provide a picture of the thermal quenching processes and activation energy levels of Nd optical centers in GaN epilayers. The results provide an important step in the realization of GaN:Nd epilayers as an optical gain medium at the infrared region.