Experimental Investigation of Optical Pulse Generation in Two-Section and Three-Section Diode Lasers with Different Configuration

In this study, optical pulses measurements obtained from two-section and three-section InGaAsP/InP diode lasers operating at a wavelength of 1350 nm are presented, with the cavity length kept constant at 315 µm, while the positions of the gain and absorber sections are varied. A 2 kHz signal with a 100 µs pulse width was applied to the gain sections along with a 20 mA DC current, while a reverse bias voltage ranging from 0 to -1.5 V was applied to the absorber section. The current applied to the gain section and the reverse bias voltage applied to the absorber section were kept constant at certain values for both laser types, and the resulting pulse amplitudes and durations were analyzed. The pulses obtained from the three-section lasers, where the absorber section was positioned in the middle (between the two gain sections), exhibited higher amplitudes than those obtained from the two-section lasers, and their pulse widths were approximately 5% narrower. In contrast, lasers with the absorber at the end produced higher output power compared to single-gain lasers, but wider pulse widths were obtained than lasers with the absorber at the middle.