Abstract

The extremely broad gain bandwidth of Ti:sapphire has made this material one of the most promising for the generation of ultrashort optical pulses.¹ Recent advances in ultrashort-pulse Ti:sapphire lasers have made it possible to routinely generate optical pulses of ~10 fs in duration, with nJ energies.²-⁵ However, many applications of ultrashort pulses such as ultrafast x-ray generation, short-wavelength lasers, XUV harmonic generation, and multi-photon ionization require higher energies, and therefore it is of great interest to amplify the low energy pulses from the laser to higher energies, while maintaining their ultrashort duration. Recently we have demonstrated the generation of 0.5 mJ, 21 fs pulses, with a near-transform limited bandwidth of 44 nm, from our amplifier system.⁶,⁷ in this paper, we present preliminary results from a second stage of amplification, which demonstrate pulse energies of up to 45 mJ, with spectral bandwidths of 37 nm. This bandwidth corresponds to a pulse duration of less than 30 fs.

© 1994 Optical Society of America