80 GHz AlGaInAs/InP colliding-pulse mode-locked laser with high pulse power

Abstract

We theoretically analyze the impact of a saturable absorber (SA) length on the pulse power of a semiconductor mode-locked laser and find that in the range of the SA length from 1.5 to 7%, a laser with a longer SA can generate pulses with a higher power. Based on the simulation, we demonstrate a colliding-pulse mode-locked laser with an 80 µm SA. The device generates pulses at 80 GHz, with a pulse width of 1.75 ps, peak power of 188 mW, pulse energy of 0.33 pJ, and time–bandwidth product of 0.51. The results provide new possibilities for the design of high-repetition frequency high-pulse power mode-locked lasers.

Quantum dot fourth-harmonic colliding pulse mode-locked laser for high-power optical comb generation

“…All SAs and gain sections are electrically interconnected through probe metal layers respectively for the convenience of butterfly packaging. While prior designs employed single SA in the center of laser cavity [25][26][27][28], our approach employs evenly distributed SAs throughout the cavity to yield more stable high-order harmonic mode-locking OFCs. To mitigate losses due to multiple SAs, the cumulative length of the three SAs is set at 10% of the total cavity length, slightly shorter than conventional typically 15%-20% design.…”

“…Typically, to generate 200 GHz repetition rate, ultra-short cavity length of 198 μm is required, which means that it could hardly achieve sufficient optical gain to lase or operate at low output power. To increase the mode spacing beyond 100 GHz meanwhile retain sufficient output power and electro-optical conversion efficiency, colliding pulse mode-locked laser (CPML) has been implemented with significant progress over the past few years [25][26][27][28]. For multi-wavelength laser source, sufficient optical output power is the major issue to be considered to overcome the insertion loss of modulators.…”