Design and characterization of a rugged and compact setup for widely tunable harmonic generation in the ultraviolet

Design and experimental characterization of a nonlinear optical converter module for the generation of widely tunable UV radiation is presented. The module combines units for second, third and fourth harmonic generation of tunable Ti:Sapphire lasers. A modified conversion scheme based on the combination of BIBO and BBO crystals reduces the complexity of our former published UV setup - resulting in a significant increase of performance and long-term stability of the system. Experimental characterization of the former and the improved UV setup are compared. The investigations of the converter module are carried out with a widely tunable Ti:Sapphire laser with nanosecond pulses and a repetition rate of 1 kHz. This laser provides a continuous tuning range of 690 nm to 1010 nm with pulse energies up to 2.0 mJ and a spectral line width of less than 10 GHz resulting in an output power of the converter module of 1000 mW, 400 mW and 200 mW respectively for the second, third and fourth harmonic generation. The new converter module is a decisive step in the development of a hands-off solid-state laser system with a continuous tuning range from the UV to the NIR - 200nm to 100 nm.