Simultaneous Two-Stokes Raman amplification in crystals

该项目的主要目标是实现和研究低束传输因子值的第一和第二斯托克斯波晶体中的同时拉曼放大。这种双斯托克斯拉曼放大将在单个拉曼放大器中实现从泵浦辐射到低发散二阶斯托克斯辐射的能量转换。放大后的二阶斯托克斯辐射具有较高的脉冲能量和较低的光束传输因子值，这对许多应用具有重要意义。例如，在硝酸钡晶体中获得的这种第二斯托克斯辐射可以有效地倍频以产生波长约300 nm的UV辐射。该波长可用于差示吸收激光雷达测量臭氧分布，作为平流层臭氧的在线辐射和对流层臭氧的离线辐射。该项目包括硝酸钡和钨酸格拉钾晶体中双斯托克斯拉曼放大的理论和实验研究。将研制的双斯托克斯拉曼放大器的工作参数与传统的第一斯托克斯高能辐射首先在拉曼激光器中产生或使用拉曼产生放大器，然后用于泵浦第二斯托克斯拉曼放大的方案进行比较，结果将用于设计一种在激光技术中有广泛应用的新型紧凑型高能固体激光拉曼放大器。

The main goal of the project is the realization and investigation of simultaneous Raman amplification in crystals of the 1st and 2nd Stokes waves with low value of beam propagation factor. This Two-Stokes Raman amplification will result in energy conversion from pump radiation into low divergent 2nd Stokes radiation in a single Raman amplifier. The amplified 2nd Stokes radiation will have high pulse energy and low value of beam propagation factor, what is important for many applications. For instance, such 2nd Stokes radiation obtained in a barium nitrate crystal can be efficiently frequency doubled to produce UV radiation with a wavelength of about 300 nm. This wavelength can be used in differential absorption LIDAR for measurement of ozone distribution as an on-line radiation for stratospheric ozone and as an off-line radiation for tropospheric ozone.The project includes both theoretical and experimental investigations of Two-Stokes Raman amplification in barium nitrate and potassium gadolinium tungstate crystals. The operating parameters of the developed Two-Stokes Raman amplifier will be compared to conventional schemes, where the 1st Stokes high energy radiation is first generated in a Raman laser or using a Raman generator-amplifier and then is used for pumping of the 2nd Stokes Raman amplification.The results will be employed to design a new class of compact, high-energy solid state laser Raman-amplifier with various applications in laser technology.