Simulation of high brightness tapered lasers

Abstract

Tapered semiconductor lasers have demonstrated both high power and good beam quality, and are of primary interest for those applications demanding high brightness optical sources. The complex non-linear interaction between the optical field and the active material requires accurate numerical simulations to improve the device design and to understand the underlying physics. In this work we present results on the design and simulation of tapered lasers by means of a Quasi-3D steady-state single-frequency model. The results are compared with experiments on Al-free active region devices emitting at 1060 nm. The performance of devices based on symmetric and asymmetric epitaxial designs is compared and the influence of the design on the beam properties is analyzed. The role of thermal effects on the beam properties is experimentally characterized and analyzed by means of the numerical simulations. Tapered lasers with separate electrical contacts in the straight and tapered sections, based on symmetrical and asymmetrical epitaxial designs are also presented and analyzed.

Simulation and geometrical design of multi-section tapered semiconductor optical amplifiers at 1.57 μm

“…An improvement of M 2 in CW conditions in comparison with pulsed conditions was reported experimentally in [15]. For the particular dimensions and material parameters of the reference tapered SOA analyzed here we observe a similar behavior.…”

“…The role of carrier lensing and thermal lensing in the beam degradation of tapered lasers has been previously analyzed by means of simulations in comparison with experimental results [13,15]. An improvement of M 2 in CW conditions in comparison with pulsed conditions was reported experimentally in [15].…”

“…The reason for using a parabolic valence band model with fitted parameters was to reduce the computational effort in the 3D simulations. Table I [15] summarizes the main physical effects included in the model and how their dependence on temperature, wavelength or carrier densities has been considered.…”

“…The simulation tool has been slightly modified in order to consider a single pass amplifier instead of a resonant cavity. The tapered laser model has been previously described in [8,9], and applied to different types of tapered lasers [11][12][13][14][15] where it has demonstrated predictive capabilities. Therefore, only basic features are described here.…”