Kosc T Z, Huang H, Kessler T J, Maltsev A, Demos S G
Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299, USA.
Rev Sci Instrum. 2020 Jan 1;91(1):015101. doi: 10.1063/1.5108506.
A specialized experimental configuration was developed to allow for more-accurate characterization of the spontaneous Raman scattering properties in anisotropic materials. This need stems from the challenges, arising from the complexity of light propagation, in obtaining accurate measurements of the angular dependence of the Raman scattering cross section in birefringent materials. The nonlinear optical material KHPO (KDP) is used as a model medium. This study is motivated by the need to improve our understanding and management of transverse stimulated Raman scattering in KDP crystals and its deuterated analog, DKDP, typically used for frequency conversion and polarization control in large-aperture laser systems. Key to this experimental platform is the use of high-quality spherical samples that enable one to measure the Raman scattering cross section in a wide range of geometries using only a single sample. The effect of polarization rotation of both the pump light and the collected Raman signal must be carefully considered in data analysis and can give rise to artifacts, which can, in part, be mitigated by reducing the input and collection cone angles.
开发了一种专门的实验配置，以更准确地表征各向异性材料中的自发拉曼散射特性。这种需求源于光传播复杂性所带来的挑战，即在双折射材料中准确测量拉曼散射截面的角度依赖性。非线性光学材料KHPO（KDP）被用作模型介质。本研究的动机是需要更好地理解和控制KDP晶体及其氘化类似物DKDP中的横向受激拉曼散射，DKDP通常用于大口径激光系统中的频率转换和偏振控制。该实验平台的关键在于使用高质量的球形样品，这使得仅用一个样品就能在广泛的几何构型中测量拉曼散射截面。在数据分析中必须仔细考虑泵浦光和收集到的拉曼信号的偏振旋转效应，这可能会产生伪像，通过减小输入和收集锥角可以部分减轻这种伪像。
