Continuous wave operation of ridge waveguide AlGaAs/GaAs distributed feedback lasers with low threshold current

Abstract
Ridge waveguide AlGaAs/GaAs distributed feedback lasers were fabricated by a two-step molecular beam epitaxial growth technique. A threshold current as low as 42 mA, which is the lowest ever reported, was obtained under a continuous wave condition at room temperature. Stable single longitudinal mode oscillation was observed in the temperature range from −20 to 30 °C without any suppression of the Fabry–Perot mode.