EFFICIENT COMPRESSION OF FEMTOSECOND PULSES BY STIMULATED RAMAN-SCATTERING

Femtosecond pulses at 496 nm were Raman-shifted in methane with 20% ef ficiency. The pulse duration could be reduced up to 6.5 times from 560 fs at the fundamental to 85 fs at the Stokes frequency (580nm), which is the shortest pulse duration generated in this way. It was shown ex perimentally that chirped-pulse Raman scattering avoids the limitation s arising from self-phase modulation.