Characterization of Three-Section Mode Locked Laser for Optical Frequency Comb Generation and Control for Space Applications

We demonstrate a three-section AlGaInAs/InP quantum well mode-locked laser diode (MLLD) operating at 1.55 μm, incorporating a saturable absorber, gain section, and modulation section. The device supports both passive and hybrid mode-locking, achieving a 15.7 GHz repetition rate with a minimum pulse duration of 1.32 ps and a time-bandwidth product of 0.91 under hybrid operation, indicating near transform-limited performance. Fixed-point analysis was performed to evaluate the dispersion characteristics and the tunability of the optical and RF frequencies under varying control parameters, highlighting the device's suitability for space applications. Additionally, we observed both multi-tone and continuous-wave (CW) optical injection locking on the same device. The injection locking aspect ratio exhibits a V-shaped spectral dependence, with a minimum at the center, and the linewidth enhancement factor was determined to be 0.33. These results demonstrate the versatility and potential of three-section AlGaInAs/InP MLLDs for use in coherent communication and frequency-comb-based systems in dynamic environments such as space.