Excitation dynamics of the 1.54μm emission in Er doped GaN synthesized by metal organic chemical vapor deposition

The authors report on the excitation dynamics of the photoluminescence (PL) emission of Er doped GaN thin films synthesized by metal organic chemical vapor deposition. Using the frequency tripled output from a Ti:sapphire laser, the authors obtained PL spectra covering the ultraviolet (UV) to the infrared regions. In the UV, a dominant band edge emission at 3.23eV was observed at room temperature; this is redshifted by 0.19eV from the band edge emission of undoped GaN. An activation energy of 191meV was obtained from the thermal quenching of the integrated intensity of the 1.54μm emission line. This value coincides with the redshift of the band edge emission and is assigned to the ErGa-VN complex level.