1.8 W, 80 MHz, picosecond, Yb-fiber-based ultraviolet sources at 266 nm

High-power, high-repetition-rate, picosecond ultraviolet (UV) sources are of great interest for scientific, industrial, and medical applications [1]. Nonlinear frequency conversion of well-established high-power solid-state lasers in single-pass configuration is an attractive approach to produce UV radiation [2]. The development of high-average-power UV sources at 266 nm through the fourth harmonic generation (FHG) of 1064 nm fiber lasers in nonlinear crystals such as β-BaB2O4 (BBO) is of particular importance due to their compact footprint, lower maintenance costs, higher efficiency, longer lifetime and excellent stability.