Second harmonic generation of spectrally broadened femtosecond ytterbium laser radiation in a gas-filled capillary

A 300-fs radiation pulse of an ytterbium laser with a wavelength of 1030 nm and energy of 150 μJ were converted to a 15-fs pulse with a wavelength of 515 nm by broadening the emission spectrum in a capillary filled with xenon and by generating the second harmonic in a KDP crystal. The energy efficiency of the conversion was 30 %.