Simultaneous Two-Stokes Raman amplification in crystals

本项目的主要目标是实现和研究低光束传输因子的一阶和二阶斯托克斯波在晶体中的同时拉曼放大。这种双斯托克斯拉曼放大将导致在单个拉曼放大器中从泵浦辐射到低发散的第二斯托克斯辐射的能量转换。放大的二阶斯托克斯辐射将具有高脉冲能量和低的光束传播因子值，这对于许多应用是重要的。例如，在硝酸锌晶体中获得的这种二阶斯托克斯辐射可以被有效地倍频以产生波长约为300 nm的UV辐射。该波长可用于差分吸收LIDAR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。该项目包括硝酸锌和钨酸钆钾晶体中双斯托克斯拉曼放大的理论和实验研究。将所开发的双斯托克斯拉曼放大器的操作参数与传统方案进行比较，传统方案首先在拉曼激光器中或使用拉曼发生器-放大器产生第一斯托克斯高能辐射，然后用于泵浦第二斯托克斯拉曼放大。高能量固体激光器拉曼放大器，在激光技术中具有各种应用。

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.