Supplementary Material

See the supplementary material for comprehensive details on the characterization of the laser wafer, including X-ray diffraction (XRD) and atomic force microscopy (AFM) analyses, which affirm the superior quality of our epitaxial layers. The material also provides a detailed explanation of the time-domain traveling-wave (TDTW) method, which was utilized to simulate the laser's performance. Additionally, it includes an in-depth discussion on the factors influencing the threshold current density and slope efficiency of our devices, substantiated by data from broad-area Fabry-Perot lasers. Furthermore, the supplementary material presents the amplified spontaneous emission (ASE) spectrum and an analysis of the experimental grating coupling coefficient, which corroborates our theoretical predictions.