Direct amplification of picosecond pulses in F{sub 2}{sup -} : LiF crystals

An amplifier of picosecond pulses with an output power up to 10{sup 10} W and an energy up to 30 mJ at 1180 nm is developed on the basis of F{sub 2}{sup -} : LiF colour-center crystals. A 3-5-ps, 0.03-mJ probe pulse at 1.18{mu}m was obtained upon intracavity SRS conversion in a passively mode-locked Nd{sup 3+} : KGd(WO{sub 4}){sub 2} laser. The F{sub 2}{sup -} : LiF crystals were pumped by 1053-nm nanosecond pulses from a Nd : YLF laser, amplified in a GLS-22 phosphate glass to an energy of 5 J. The probe SRS pulses were amplified in a four-crystal two-cascade amplifier based on F{sub 2}{sup -} : LiF crystals with the total length of the active medium of 360 mm, by using counterpropagating pump beams. The dependences of the output radiation energy on the pump and input signal energies are measured. (special issue devoted to the 90th anniversary of a.m. prokhorov)