Self-pulsation in InGaN laser diodes with saturable absorber layers

Self-pulsating InGaN laser diodes with a p-type InGaN saturable absorber (SA) layer are demonstrated. The SA layer consists of a 1-nm-thick p-type InGaN well surrounded by 2-nm-thick p-type In0.02Ga0.98N barriers. The lower barrier of the SA is located on the 18-nm-thick p-type Al0.3Ga0.7N evaporation-prevention layer of the active region. Self-pulsation is demonstrated for output powers in the range 4 to 22 mW with corresponding self-pulsation frequencies in the range 1.6 to 2.9 GHz. Results indicate that the position of the SA layer in the structure has a strong influence on the carrier lifetime and is responsible for the observation of self-pulsation in these devices.