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Results of statistical analysis for beam resistance tests obtained for a new KGSS-0180 neodymium glass are presented. Methods of determining limitations for admissible levels of radiation energy density in the active elements of laser systems based on calculation of statistics for the first term of an ordered data series on glass damage thresholds are proposed. Use of this approach to minimize the impact of "size dependence" on accuracy of determination of a minimal threshold value is considered.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Laser power of more than 100TW (70fs, 10J) has been achieved in experiments on optical parametric amplification of femtosecond pulses in KD*P crystals. Energy conversion efficiency of optical parametric amplifier is 27%.

Results of fast light ion yield measurements are presented. Laser-plasma experiments were carried out on picosecond laser PROGRESS-P at laser intensities on a target to be 1 ÷ 4•1018 W/cm2. Ring image and extremely small angular divergence of fast ion beam were found. Hard ions with energy more than 8 MeV were recorded. Model of fast ion generation is discussed and typical energy and spatial distribution of fast ion extension are estimated.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This work presents a method for determination of specific amplification coefficient for stimulated Brilloin scattering (SBS) of radiation based on measuring amplification of the Stokes signal in a medium sample used as the SBS-amplifier. Registration of spatial distributions of amplified beam intensity allows minimization of a measurements error caused by saturation of Stokes radiation amplification in the sample under study. Values of specific amplification coefficient for SBS of radiation are obtained under identical experimental conditions for new phosphate glass KGSS 0180 (g = 1.9 cm/GW) and for glasses widely used in laser systems: GLS 22 (g = 1.4 cm/GW) and K 8 (g = 1.3 cm/GW). By means of optical heterodyning of radiation a SBS-frequency shift of laser radiation at a wavelength of 1.054 microns is measured for new glass KGSS 0180 (▵v = 14.57± 0.02 GHz). It makes it possible to estimate hypersound propagation velocity in the tested glass (V ≈ 5030 m/c) at this frequency.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Method for measuring nonlinear refractive index (n2) of optical materials is presented. It is based on the analysis of large scale beam distortions caused by the nonlinear aberrational lens induced by power radiation in the medium under study. Absolute n2-values for new Russian laser phosphate glass KGSS 0180/35 (n2 ≈ 1.2"10-13 CGSE units) and widely used glasses GLS 22 (n2 ≈ 1.9"10-13 CGSE units) and K8 (n2 ≈ 1.4"10-13 CGSE units) were obtained with this method for laser pulse duration of 4 ns. Also, evaluation of nonlinear phase delay induced in the laser beam that has passed through the glass samples under study for a longer pulse duration of -up to 25 ns has been performed.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A laser system designed for complex testing of optical elements, such a determination of a nonlinear refraction index, a specific coefficient of radiation amplification under stimulated Brillouin scattering (SBS), optical elements surface damage threshold and establishment of platinum inclusions in active elements is described. Descriptions of measurement techniques and results obtained for widely used in multi-stage Nd-glass laser systems glasses, including new phosphate glass KGSS-0180, are presented.