Froula D H, Divol L, Berger R L, London R A, Meezan N B, Strozzi D J, Neumayer P, Ross J S, Stagnitto S, Suter L J, Glenzer S H
L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
Phys Rev Lett. 2008 Sep 12;101(11):115002. doi: 10.1103/PhysRevLett.101.115002. Epub 2008 Sep 10.
We demonstrate a significant reduction of stimulated Brillouin scattering by polarization smoothing in large-scale high-temperature hohlraum plasma conditions where filamentation is measured to be negligible. The stimulated Brillouin scattering experimental threshold (defined as the intensity at which 5% of the incident light is backscattered) is measured to increase by a factor of 1.7+/-0.2 when polarization smoothing is applied. An analytical model relevant to inertial confinement fusion plasma conditions shows that the measured reduction in backscatter with polarization smoothing results from the random spatial variation in polarization of the laser beam, not from the reduction in beam contrast.
我们证明，在大规模高温黑腔等离子体条件下，当测量到丝状化可忽略不计时，通过偏振平滑可显著降低受激布里渊散射。测量发现，应用偏振平滑时，受激布里渊散射实验阈值（定义为5%的入射光发生背向散射时的强度）提高了1.7±0.2倍。一个与惯性约束聚变等离子体条件相关的分析模型表明，测量到的偏振平滑使背向散射减少是由于激光束偏振的随机空间变化，而非光束对比度的降低。
