Impact of Nitrogen on the lasing characteristic of 1.3 µm GaInNAs quantum well lasers

Abstract

A comprehensive study has been done to investigate the lasing characteristic of 1.3 µm GaInNAs quantum well (QW) lasers. We have varied the Nitrogen (N) compositions in GaInNAs QW with N=1.0≤x≤2.0. Significant improvement of lasing wavelength, emission efficiency and output power were demonstrated with higher N compositions. The emissions wavelength red shifted linearly when the N compositions enlarge. As formerly known, the band gap of GaInNAs is controlled by adjusting the ratio of group III (Ga, In) or group V (N, As) materials. As the N increased, the band gap will reduce and the emission wavelength increased.The average ratio of the red-shifted is 92.49 nm per N percentage. The PL intensity seems to reduce with higher N which due to the deteriorates crystal quality at higher N incorporation. We believed that that the optical quality of the GaInNAs QW depends on N compositions and total number of N incorporated in the QW. The strain profile between QW and the surrounding matrix has a major effect on the optical quality of GaInNAs QW. However the structural qualities such as homogeneity, strain fluctuation and interface roughness will degrade with too much N composition, hence reduce the threshold current, and increased the external differential quantum efficiency. Further comparisons on the devices performance will be report further.