RESUMO
We present an external cavity in a quasi-Littrow configuration for a diode laser bar with 19 single emitters and the individual spectral stabilization, ranging from wavelengths between 970 and 980 nm corresponding to each emitter. The imaging of the vertical waveguide mode onto a blazed grating acting as a diffractive optical element is realized with a beam transformation system that swaps the vertical and lateral axes. Along with a feedback intensity of <10%, the reduction of the divergence due to a beam expander results in high losses for cross coupling modes. We demonstrate the possibility to suppress cross coupling and that even a process-related small smile error has a positive effect on the quality of the spectral stabilization in a quasi-Littrow configuration.
RESUMO
We demonstrate spectral beam combining of a 980 nm tapered diode laser bar. The combined beam from 12 tapered emitters on the bar yielded an output power of 9.3 W at 30 A of operating current. An M2 value of 5.3 has been achieved along the slow axis. This value is close to that of a free running single tapered emitter on the bar at the same current level. The overall spectral beam combining efficiency was measured to be 63%.
