56 kW peak power, nanosecond pulses at 274 nm from a frequency quadrupled Yb-doped fiber MOPA
A 2 W deep-ultraviolet (DUV) source at 274 nm with 5.6 kW peak power is demonstrated by frequency quadrupling a diode-seeded, polarization-maintaining (PM), Ybdoped fiber master oscillator power amplifier (MOPA) system delivering 1.8 ns pulses at a repetition rate of 200 kHz. The second harmonic generation (SHG) and the fourth harmonic generation (FHG) are achieved by using Lithium Triborate (LBO) crystal and β−BaB 2 O 4 (BBO) crystal in sequence, with an IR-to-green and green-to-UV conversion
... n-to-UV conversion efficiency of up to 65% and 26%, respectively. This is the first kW peak power pulsed UV system reported at 274 nm which has great potential for machining insulators, 2D materials, isotopic separation of Calcium-48, and fluorescence analysis of biological molecules. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. "High-quality and high-efficiency machining of glass materials by laser-induced plasma-assisted ablation using conventional nanosecond UV, visible, and infrared lasers," Appl. Phys., A Mater. Sci. Process. 69(7), S879-S882 (1999). 2. O. M. Kirkby, M. Sala, G. Balerdi, R. de Nalda, L. Bañares, S. Guérin, and H. H. Fielding, "Comparing the electronic relaxation dynamics of aniline and d(7)-aniline following excitation at 272-238 nm," Phys. Chem.