Design optimization of InGaAsP/InP heterostructures of high-power laser diodes emitting at a wavelength of 1.55 $\mu$m

The study aims to optimize the design of semiconductor laser heterostructures based on InGaAsP/InP, emitting in the eye-safe wavelength range of 1.55 $\mu$m in pulsed mode. The research was conducted using a developed two-dimensional laser diode model that accounts for drift-diffusion carrier transport in the direction perpendicular to the heterostructure layers and the inhomogeneous photons distribution along the resonator axis. For model laser diodes with an emitting aperture width of 100 $\mu$m, the main loss mechanisms were studied, as well as their effect on the output optical power at a pulse pump current of 150 A. The study involved multiparametric optimization, taking into account the influence of the bandgap width and waveguide thickness, as well as the position of the active region within the waveguide layer. A strong dependence of the optimal waveguide width on its band gap, as well as the optimal band gap providing a balance between the main power limiting mechanisms, was established. It is shown that, regardless of other parameters, the location of the active region near the p-emitter is preferable.