Multiple-pass Raman gain cell

The application of a multiple-pass Herriott cell to stimulated Raman scattering (SRS) is evaluated and demonstrated. The cell combines a long optical path length with periodic refocusing to enhance Raman gain. This technique is especially useful for reducing SRS threshold pump power in the IR where the Raman gain is low. This paper presents an analysis and design procedure for a multiple-pass Raman gain cell and gives experimental results for SRS in H(2) gas.