Abstract

The generation of ultra-intense pulses with pulse durations of ~100 fs has so far concentrated on Ti:sapphire systems. Typically, pulse energies of 50-200 mJ can be generated with these systems, mostly limited by the aperture size of available high quality crystals, which is currently ~1 cm.¹ Recently, Cr:LiSAF has received attention as an alternative material for high-intensity⁷ femtosecond pulse amplification. This material has a large spectral bandwidth which enables the amplification of sub-100 fs pulses, and, moreover, is amenable to flashlamp pumping. Regenerative amplification of femtosecond pulses has been demonstrated using Cr:LiSAF-producing pulses in the mJ range.^2,3 Recently, a 95 mm × 120 mm Cr:LiSAF amplifier was used to increase the output of a 120 fs Tr:sapphire system from 45 to 150 mJ.⁴ We are now able to fabricate Cr:LiSAF rods with diameters up to 25 mm offering the possibility to amplify femtosecond pulses to the joule range.

© 1993 Optical Society of America