DOI: 10.17035/cardiff.29591231.v1
title: On-chip gain elements for integrated photonics _ Data

description: This dataset supports the study On-chip gain elements for integrated photonics, which investigates quantum dot–based III–V gain chips incorporating multimode interference reflectors (MMIRs) for hybrid integration with silicon photonic integrated circuits. The data include numerical simulations and experimental measurements of MMIR laser structures designed to reduce mirror loss, suppress higher-order modes, and improve threshold current and slope efficiency in the O-band. Included are raw power–current characteristics, temperature-dependent laser performance, emission spectra, mode spacing analysis, reflectivity simulations, and net modal gain measurements. These datasets provide full numerical values underlying all figures and tables in the associated publication. The data in each txt files are provided as follows:fig 2.txt: This file contains the numerical data used to calculate the threshold gain requirement as a function of coupling efficiency between the III–V gain chip and the passive silicon circuit. Data are provided for different mirror reflectivities (30%, 50%, and 90%) based on Eq. (1).fig 4.txt: This file contains simulation results (using Fimmwave, Fimmprop and OmniSim software from Photon Design) for the 1-port MMIR design, including output power distribution versus MMI length, reflectivity dependence on mirror angle, and wavelength-dependent reflectivity performance. These data support optimisation of the MMIR reflector geometry.fig 5.txt: This file contains simulation datasets (using Fimmwave, Fimmprop and OmniSim software from Photon Design) for the 2-port MMIR design, including output power splitting, mirror reflectivity versus angle, and wavelength dependence. These results demonstrate the reflector performance and optimisation of the MMIR reflector geometry.fig 6.txt: This file contains mode propagation and reflectivity simulation data for different transverse modes (TE00, TE01, TE02) within the MMIR structure. The data demonstrate the mode-selective filtering effect of MMIRs and suppression of higher-order modes.fig 9.txt This file contains raw experimental power–current (P–I) measurements at 25°C for MMIR lasers (Types A, B, C) and reference Fabry–Perot ridge waveguide lasers. Data include threshold currents and slope efficiencies demonstrating improved performance with MMIR mirrors. Note the power here is the average power not the peak power.fig 10.txt: This file contains temperature-dependent P–I measurement data for MMIR and FP-RWG lasers across multiple operating temperatures. The data illustrate reduced thermal sensitivity of threshold current in MMIR-based laser cavities.fig 11.txt: This file contains threshold current density data as a function of temperature and cavity length for MMIR and FP-RWG lasers. These results quantify the benefits of reduced mirror loss and improved gain efficiency in MMIR devices.fig 12.txt: This file contains spectral measurement data showing peak lasing wavelength as a function of temperature for MMIR and FP-RWG lasers.fig 13.txt: This file contains emission spectra datasets for MMIR lasers (Types A, B, and C) at 25°C. Data include longitudinal mode structure and confirm suppression of higher-order lateral modes due to MMIR mode filtering.fig 14.txt: This file contains emission spectra datasets for Fabry–Perot ridge waveguide reference lasers of different cavity lengths.fig 15.txt: This file contains the peak of net modal gain measurement data obtained using the segmented contact technique, plotted alongside calculated mirror loss and threshold current density. These results show MMIR lasers operate in a favourable gain regime with reduced saturation.table 1.txt: This file contains experimentally derived and theoretically calculated external differential efficiency values for FP-RWG and MMIR lasers of different cavity lengths. Data include slope efficiency, mirror loss contributions, and comparisons with model predictions.table 2.txt: This file contains experimental and theoretical longitudinal mode spacing values for MMIR lasers Types A and B. Data were derived from measured spectra and calculated using Eq. (3), confirming cavity operation characteristics of the MMIR designs.