Stimulated Brillouin and Raman scattering for the generation ofshort excimer laser pulses

In this experimental work, the SBS and SRS processes were used in order to produce UV laser beams of good optical quality and short time duration. An XeCl oscillator and a double-pass amplifier with a phase-conjugate mirror via stimulated Brillouin scattering, generate the laser beam at 308 nm to pump a Raman cell. The oscillator pulse was 11 ns long, while the amplified phase-conjugate beam duration could vary from 3.3 to 1.5 ns, due to the compression operated by the Brillouin mirror. When this last laser beam was focused into a Raman cell containing methane at 30 atm, the shortest backward stimulated Raman scattering pulse at 338.4 nm was 170 ps long with 0.4 ml of energy. The 338.4-nm wavelength is interesting for the production of short bunches of cold electrons from Mg and Zn targets