Optical Amplification from Er Optical Center in GaN in the Visible region

Optical amplification from Rare-earth doped GaN semiconductor has been demonstrated in the visible region. We have reported a stronger emission and an optical amplification in GaN:Er materials synthesized by sputtering under the resonant excitation via the higher-lying inner 4f shell transitions and the band-to-band excitation of the GaN host. The observation of the optical amplification has been demonstrated through characteristic features of threshold behavior of emission intensity as a function of optical pump power. Employing the transient time-resolved photoluminescence technique, we have discovered the temperature independence of the photoluminescent decay dynamics for both isolated-Er and defect related optical centers in GaN. The optical amplification in GaN semiconductor opens up new possibilities for extended functionalities and integration capabilities for optoelectronic devices.