Measurements of gain spectra over wide spectral ranges in GaInAsP/InP multiple-quantum-well laser diodes
01 January 2008
Gain spectra of 1500-nm-wavelength GaInAsP/InP multiple-quantum-well (MQW) laser diodes were obtained over wide wavelength and injection current ranges. To cover wide spectral ranges, we combined gain spectra derived from amplified spontaneous emission (ASE) spectra and white-light transmittance spectra. In addition, gain (absorption) spectra for very low injection currents were obtained through ASE measurements using a liquid-nitrogen-cooled InGaAs photodiode array detector with high sensitivity. From these gain spectra, accurate estimations of the material gain and carrier-density-dependent internal loss as well as the material-transparency current were obtained.