High-Brightness Quantum Well Tapered Lasers

High-power quantum well lasers with high brightness in the spectral range between 650 nm and 1080 nm will be presented. Improved layer structures with a narrow vertical far-field divergence down to angles of 15 $^{\circ}$ (full-width at half-maximum) were developed. For these layer structures, optimized tapered lasers were processed to achieve laterally a nearly diffraction-limited beam quality with beam propagation factors smaller than 2. Depending on the emission wavelength, the tapered devices reach an output power up to 12 W and a brightness of $\hbox{1 GW}{\cdot}\hbox{cm}^{-2}{\cdot}\hbox{sr}^{-1}$.