High-power spatially single-mode diode lasers at 15xx nm wavelengths are of interest for Light Detection and Ranging (LIDAR) at eye-safe wavelengths, as pump lasers for Raman and rare-earth doped fiber amplifiers as well as for material processing. A cost-efficient way to realize high-power in combination with high-brightness is the tapered resonator concept. We demonstrate InGaAsP/InP based diode lasers and tapered amplifiers with fast axis far fields of 36° FWHM and wavelengths around 1550 nm which were grown by MOCVD. From processed broad area lasers with 2mm resonator length and 100µm stripe width and 1mm long ridge-waveguide lasers, parameters for the logarithmic gain model are evaluated. With their implementation in 2-dimensional BPM simulations, an optimized resonator geometry has been derived for aiming 1W in cw operation and 2W in pulsed mode. The optimised design consists of a ridge section length of 310µm and a taper section length of 2190μm. Different taper designs have been processed and investigated in detail. In dependence on the taper angle ridge widths are between 4 and 5μm. For narrow-linewidth operation, the tapered devices are provided with anti-reflection coatings of less than 0.01% on the rear facets and spectrally stabilized with an external grating. Beside the electro-optical characterisation, beam quality has been characterized in terms of beam waist analysis and M2.
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