Multiple ultrashort pulse damage of coated beta barium borate

Kurzfassung

An investigation of ultra short pulse damage threshold of AR coated beta-barium borate (BBO) used for SHG or as Q-switching material has been carried out. As a laser source, a CPA Ti:Sapphire laser system operating at a wavelength of 775 nm tuned to various pulse durations (150 fs, 1 ps, 3 ps) has been used. The online damage detection system is based on a scatter probe unit. It is capable of counting the number of pulses prior to damage and logging of the damage level, and allows the interruption of irradiation immediately after damage. For S-on-1 irradiation and pulse numbers of 104 per site, a LIDTs of 0.3, 0.8 and 1.9 J/cm^2 were detected for the given pulse durations.Characteristic damage curves were measured according to the ISO standard 11254 2.0. Coating delamination was observed as the damage morphology.