1：Experimental Design and Method Selection:

The study involved the fabrication of two-section narrow ridge passive mode-locked lasers from InP/GaInP quantum dot material. The mode-locking conditions were investigated for devices with different cavity lengths.

2：Sample Selection and Data Sources:

The laser structures were grown on n-GaAs (100) substrates oriented 10° off toward <111> direction by MOCVD. Self-assembled InP QDs were covered by lattice-matched GaInP quantum wells to form each DWELL layer.

3：List of Experimental Equipment and Materials:

The sample material was patterned with 2 μm wide shallow-etched ridges by electron beam lithography and inductively coupled plasma (ICP) etching. Benzocyclobutene (BCB) was used for planarization, and reactive ion etching was used for etch-back. Cr/Au were deposited as p-contact metals.

4：Experimental Procedures and Operational Workflow:

The fabrication process included patterning, etching, planarization, contact metal deposition, and annealing. The mode-locking conditions were measured using a fast-photodetector connected to an electrical spectrum analyzer.

5：Data Analysis Methods:

The optical gain and absorption spectra were determined using the segmented contact method. The mode-locked pulse repetition frequency was measured and analyzed.