Generation of femtosecond laser pulses at 263 nm by K3B6O10Cl crysta**Project supported by the National Key Basic Research Program of China (Grant No. 2013CB922402), the Key Program of the National Natural Science Foundation of China (Grant Nos. 11434016 and 61575219), and the International Joint Research Program of the National Natural Science Foundation of China (Grant No. 61210017).

Abstract

The third harmonic generation (THG) of a linear cavity Ti:sapphire regenerative amplifier by use of a K3B6O10Cl (KBOC) crystal is studied for the first time. Output power up to 5.9 mW is obtained at a central wavelength of 263 nm, corresponding to a conversion efficiency of 4.5% to the second harmonic power. Our results show a tremendous potential for nonlinear frequency conversion into the deep ultraviolet range with the new crystal and the output laser power can be further improved.