Femtosecond and picosecond stimulated Raman scattering in gas mixtures

Summary form only given. Stimulated Raman scattering (SRS) in gases is a versatile method for frequency conversion of femto- and picosecond pulses in the broad spectral range from UV to near IR. Previously we have shown that in single component gases such as H/sub 2/, D/sub 2/, HD and CH/sub 4/, in the transient excitation regime, SRS can result in efficient conversion of 400 nm pulses into a set of Stokes- and anti-Stokes components, defined by the molecule´s vibrational and rotational frequencies. In this paper we observe transient SRS at combinational frequencies in dual mixtures of Raman-active molecules, such as H/sub 2/-D/sub 2/, H/sub 2/-HD, H/sub 2/-CH/sub 4/ and D/sub 2/-HD. This allows us to extend the range of the new frequencies, by including shifts v=iv/sub 1/+jv/sub 2/ (i,j=0, /spl plusmn/1, /spl plusmn/2, ...), where v/sub 1/ and v/sub 2/ are the Raman frequencies of the first and the second molecule.