高功率光纤激光反常受激拉曼散射机理研究

项目名称： 高功率光纤激光反常受激拉曼散射机理研究

项目编号： No.11504026

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 柯伟伟

作者单位： 北京应用物理与计算数学研究所

项目金额： 16万元

中文摘要： 高功率光纤激光在包括工业加工、基础科研、国防反恐等众多领域都得到了广泛应用，近年来发展迅猛。由于高功率光纤激光器是一个多物理过程的复杂耦合系统，不断涌现中各种新的物理现象，最近我们在一系列无相关性的实验中观察到的反常前向受激拉曼散射（SRS）就是其中之一。它表现为在远低于理论预期的功率水平下即观测到SRS，同时可能伴随着反Stokes光的出现。另一方面，SRS也是制约高功率光纤激光功率进一步提升的核心因素。本课题拟以高功率光纤激光中的受激拉曼散射为研究对象，系统深入研究其中的影响因素，特别针对反常前向SRS现象，采用理论与实验相结合的方式，揭示该现象的物理机理。基于此提出高功率光纤激光中SRS抑制的新思路，并探索它在拉曼光纤激光器中的应用。

中文关键词： 高功率光纤激光器；受激拉曼散射；四波混频；多模光纤

英文摘要： High power fiber lasers have attracted a lot of attentions due to its widely potential applications in many fields, such as industrial processing, scientific research and national defense. Because it is a complex coupling system with multi-physical process, high power fiber lasers exhibit many brand new physical phenomena, one of which is the abnormal forward stimulated Raman scattering (SRS) observed in several independent experiments very recently. It shows that the SRS power threshold is much lower than the theoretical prediction and the anti-Stokes wave can be observed under some conditions. On the other hand, SRS is an important factor which limits the power scalability of high power fiber lasers. In this research project, we focus on the SRS process within high power fiber laser, especially the abnormal forward SRS phenomenon. The physical mechanism will be studied systematically with the combination of theory and experiment. New ideas of SRS suppression in high power fiber lasers will be proposed and its application in Raman fiber laser will be explored as well.

英文关键词： high power fiber lasers;stimulated Raman scattering;four wave mixing;multi-mode fibers