Stimulated Raman effect and four-wave mixing in a hollow waveguide

A theoretical and experimental investigation of stimulated Raman scattering and four-wave mixing in a gas-filled hollow waveguide was performed. The four-wave mixing processes, specifically the generation of the third Stokes component at omega /sub 3/ when omega /sub 3/=2 omega /sub 2/- omega /sub 1/, show a strong resonance-like behavior as a function of wavelength. These resonances are caused by the phase matching required for efficient four-wave mixing, because the hollow waveguide supports only certain propagation directions leading to the development of waveguide modes. The theoretical results are compared with experimental data for TEM/sub 00/ and TEM/sub 10/ fundamental dye-laser beams generating third Stokes wavelengths between 2.6 and 7.5 mu m.<
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