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Processes of the optic pump energy transformation in system Raman converter -wideband laser medium with homogeneously broadening amplification band have been investigated. Raman converter and wideband medium were used in common cavity. As a Raman converter a barium nitrat and benzol were used, as a wideband media a LiF crystals with F or F2 color centrs and oxazyn-l were used. Thank to four-levels excitation scheme of the wideband media, pump output excitation threshold of them is less than for SRS excitation. In such system generation start from the wideband medium. The wideband medium amplify seeding radiation of the Raman converter at the Stokes frequences, which get to the amplification band of the wideband medium. Then, thank to additional Raman amplification, condensation of the wideband generation spectrum arise. Thus the threshold of the SRS excitation decreased and efficiency of the SRS increased in Stokes or anti-Stokes regions.Under certain conditions in liquid Raman media arised generation on the different types of the vibrations and generation on the combined frequences too.Stimulated Raman Scattering (SRS) widely used for control of the laser generation parametrs, transformation ofthe frequency, increase of the bright and others 1,2 Along with undoubted advantages of this method coherent radiation frequency transformation, in the wide spectral region from ultraviolet up to infrared , it have essential deficiences, in particular great pump thresholdes, that necessary focusing of the pump beams and SRS complicated by the cascade transformation into highest Stokes components. This deficiences essential complicate use of this method, moreover often do its use impossible. In our early papershave been shown possibility of the amplification of the weak coruning and contraruning SRS seed from the Ba(NO3) crystal by meanse of the LiF crystal with F color centers (CC), that allow reach of high efficiency ofthe trasformations pump energy into Stokes generation component without pump beam focusing.In this paper the transformation processes of the optic pump energy in the systems: Raman converterwideband electron-phonon medium have been investigated and mechanism ofthis effect was propoused. THEORYThe propagation of light waves in a medium is discribed by equation for electric field E .For simplification vector sign did't write. n2d2E -4n dP1 ----c-dt c dt where p -the nonlinear polarization, n -the refractive index , c -the velocity of light in vacuum. In our case electrical fild possible to discribe by the plane waves with slowly varying amplitudes and phases wich propogate along z -direction of the medium. E(z,t) = 1 / 2 E1 exp[i (Ic1 z -o t)] + 1 / 2 E exp[i (k z -co t)] + 2 +1/2 Ea e[i(k zi t)]+c.c., 468 ISPIE Vol. 2700 0-8194-2074-3196/$6.00 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/26/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

The process of the optic pump energy transformation in the system with temperature tuning phase-matching LiNbO3 crystal and LiF: F or F wideband laser medium with homogeneous broadening of the amplification band have been investigated. Nonlinear crystal and wideband medium was placed in the common cavity. Excitation threshold of the wideband medium generation more lower than one for parametric generation, that is why generation of the system start from wideband generation. Wideband radiation seed of the OPO signal wave and excitation threshold of the system reduced. During the generation development, when the system radiate near OPO lines, additional amplification at OPO frequences bring to effect of condensation wideband spectrum.Wavelength turning in the region O,82-l.lim was obtained by OPO in system on the base LiNbO3 and LiF: F crystal in common cavity at 0,532 im pumping.Wavelength turning in the region 1 .1-1.26 m was obtained by OPO in system on the base LiNbO3 and LiF: F crystals in common cavity at two-waves pumping (0,532 and 1 ,O64j.m) . The generation threshold of the such system is essentialy less than for OPO on the base LiNbO3 only.Optical parametric oscilation (OPO) with nanosecond puls pumping is one of the perspective sourses of tuning radiation. To obtaining high efficiency pump energy transformation into turning radiation is connected with initial level of seeding radiation. At the expense of generation the time develope decreasing it bring to threshold reduction 1,2 3.THEORYThe parametric generation is a three-wave processs, in which under wave with frequency 03 the more weak waves o and (02 generate according to correlation: 312(1) This waves interact through nonlinear polarization pnl which square-low depend on pump electric field E:where ,' -the nonlinear media susceptibility.The amplitudes three-wave equation we can write as :dz 0-81 94-2072-71961$6.0O SPIE Vol. 2698 / 229 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/16/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

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