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Diode lasers generating optical pulses with high peak power and lengths in the nanosecond range are key components for light detection and ranging systems, e.g. for autonomous driving and object detection. We present here an internally wavelength stabilized distributed Bragg reflector broad area laser bar with 48 emitters. The vertical structure based on AlGaAs (confinement and cladding layers) and InGaAs (active quantum well) is specifically optimized for wavelength-stabilized pulsed operation, applying a surface Bragg grating with high reflectivity. The bar is electrically driven by a new in-house developed high-speed driver based on GaN transistors providing current pulses with amplitudes of up to 1000 A and a repetition frequency of 10 kHz. The generated 4 ns to 10 ns long optical pulses are nearly rectangular shaped and reach a pulse peak power in excess of 600 Watts at 25 °C. The optical spectrum with a centre wavelength of about 900 nm has a width of 0.15 nm (FWHM) with a side mode suppression ratio > 30 dB. [ABSTRACT FROM AUTHOR]

We theoretically analyze the influence of nonlinear effects such as spatial holeburning, two-photon absorption and gain compression on the power-current and beam characteristics of a high-power broad-area distributed Bragg reflector laser with a stripe width of 50 μm operated in pulsed mode and compare them with simulations of a similar Fabry-Pérot laser. On the one hand, spatial holeburning leads to a higher mean intensity within the cavity for a Fabry-Pérot laser and resulting higher losses in combination with two-photon absorption and gain compression, on the other hand, excitation of higher order lateral modes leads to losses through the Bragg grating. In combination with spatio-temporal power variations resolved by the utilized time-dependent traveling wave model two-photon absorption leads to higher power losses compared to those models using averaged powers. [ABSTRACT FROM AUTHOR]