Preparation and properties of Mn-doped GaN powders

Abstract GaMnN powders with varying Mn concentrations (0–7 at. %) were prepared by the Sol-Gel method. All samples are found to have a hexagonal wurtzite structure without any secondary phases. Photoluminescence spectra show a redshift in the peak position of the UV PL with increasing Mn doping which is consistent with the band gap narrowing. X-ray photoelectron spectroscopy (XPS) measurements show that the doped Mn ion in (Ga, Mn)N powders is in the divalent state. Magnetism measurements revealed that all samples are paramagnetic at 5 K and that the Curie–Weiss temperature is negative.