Spectral characteristics of single-frequency quantum-well heterolasers

Precision measurements and a comparative analysis were made of the emission spectra of GaAs\/AIGaAs and InGaAs\/GaAs heterostructure injection lasers with quantum-well active layers and plane—plane cleaved cavities. Attention was focused on the correlation between the linewidth enhancement factor and the parameters of single-frequency lasing. Single-frequency emission at λ = 975 nm was observed for a quantum-well laser with strained active layers and a cw output power in excess of 100 mW was reached when the side longitudinal modes were suppressed by more than 30 dB.