全固态自拉曼飞秒激光技术的研究

By theoretical and experimental methods, all-solid-state self-stimulating Raman femtosecond lasers can be built up. The SRS process in the cavity of the mode-locked oscillator, and the interaction between solitons and the SRS, are analysed. Influences of factors including the SRS gain, the linear loss, the nonlinear effect, the saturable absorption, the dispersion, and the repetition frequency, on the mode-locked operation, the SRS frequency converting, and output properties are investigated. And dynamics of effects of several parameters are researched. A steady operation and a high-efficient output can be achieved through optimizing parameters such as the length of the gain material, the negative dispersion, the modulation depth of the SESAM, and the output coupler.

本课题拟是利用掺镱钨酸盐晶体既是超短脉冲激光材料，也是受激拉曼散射（SRS）非线性材料的双重特性，研究全固态自拉曼飞秒激光技术，即：在半导体泵浦的全固态飞秒激光技术的基础上，利用激光晶体自身受激拉曼散射效应实现频率变换，获得SRS飞秒激光。并通过倍频技术获得黄光波段的飞秒激光输出，开发结构简单、紧凑、高效的全固态飞秒黄光激光系统，开拓全固态飞秒激光技术更广阔的应用前景。.采用理论和实验相结合的方式，建立全固态自拉曼飞秒激光系统。重点研究锁模激光器腔内受激拉曼散射的物理过程，分析孤子锁模运转与受激拉曼散射的互作用过程。研究拉曼增益，线性损耗，非线性效应、饱和吸收条件、色散补偿、重复频率等因素，对激光器锁模运转、SRS非线性频率变换、激光输出特性的影响，探索各物理参数相互影响的动力学过程。通过优化增益介质长度、负色散量、SESAM调制深度、耦合输出比等器件参数，实现激光器的稳定运转与高效输出。

本课题利用掺镱钨酸盐晶体既是超短脉冲激光材料，也是受激拉曼散射（SRS）非线性材料的双重特性，研究全固态自拉曼超短脉冲激光技术，并通过倍频技术获得黄光波段的激光输出。研究锁模激光器腔内受激拉曼散射的物理过程，分析锁模运转与受激拉曼散射的互作用。研究拉曼增益、色散补偿等因素，对激光器锁模运转、非线性频率变换的影响。同时研究了掺钕钨酸盐晶体超短脉冲在同带泵浦下，超短脉冲运转中的受激拉曼散射特性。课题实现了1140nm、570nm等特殊波长的脉冲激光运转。