Ridge waveguide AlGaAs/GaAs distributed feedback lasers with multiple quantum well structure

Abstract
Ridge waveguide AlGaAs/GaAs distributed feedback lasers with multiple quantum well structure were fabricated for the first time. The threshold current of 28 mA, which is the lowest ever reported among AlGaAs/GaAs distributed feedback lasers, was obtained at room temperature. Stable single longitudinal and transverse mode oscillation was observed over the wide temperature range. The dynamic linewidth was also measured and it was five to six times smaller than that of a double heterostructure distributed feedback laser.