Raman frequency shifter for laser pulses shorter than 100 fs.

The technique of frequency shifting of sub-100 fs laser pulses was developed. It is based on the stimulated Raman scattering pair of chirped laser pulses with orthogonal polarization. The 50 fs laser pulse at the wavelength of 810 nm was converted to 68 fs Stokes pulse at the wavelength of 1060 nm with energy conversion efficiency of 20%.