Stimulated Raman scattering of high pressure gas in multiple-pass configuration

SRS (Stimulated Raman Scattering) is a very effective method to expand the spectrum range of high power laser, especially in the regime of near IR and middle IR. In this paper SRS of high pressure H2 and D2 with MPC (multiple-pass cell) configuration were reported. Relation of (FS1) first forward Stokes and (BS1) first backward Stokes has been analysis. The process of gain of FS1 was explained. Experimental results also indicated the second Stokes was also generated. D2 SRS of the fundamental output of Nd:YAG laser generates the second Stokes light of 2.92 m. The lasers with wavelength of 2.9 μm have broad applications. Finally, multiple-pass SRS was better for complete conversion of pump laser.