Comparative theoretical investigation of passively mode-locked diode lasers with different cavity configurations

In this study, modelling results of 1550 nm AlGaInAs/InP passively mode-locked semiconductor lasers with two gain sections and one absorber section are reported using propagation wave equations according to different lengths and positions of the these sections. Comparative results of output power, carrier number and pulse width of three section semiconductor lasers are obtained using different cavity lengths. It has been found that three-section lasers with a longer first gain section have higher output power of 920 mW and shorter pulse durations of approximately 1.57 ps. When the current and voltage are kept constant, higher output power and higher electric field are obtained as the cavity length gets shorter.