传输极限皮秒脉冲光纤放大的理论和实验研究

项目名称： 传输极限皮秒脉冲光纤放大的理论和实验研究

项目编号： No.61275109

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 无线电电子学、电信技术

项目作者： 赵鹭明

作者单位： 江苏师范大学

项目金额： 80万元

中文摘要： 本项目针对皮秒脉冲放大难以兼顾大功率放大和获得传输极限放大脉冲的问题，提出和研究从根本上克服非线性效应对放大脉冲的光谱展宽、大幅提高放大脉冲的脉冲能量和峰值功率并同时获得好的光束输出质量的新技术方案。其核心是在放大前将皮秒种子脉冲等分复制成小脉冲串并加以时延，经光纤放大后再补偿时延并叠加所有放大脉冲从而获得具有高峰值功率的传输极限皮秒脉冲，除使用大模场面积增益光纤降低非线性效应外，还通过使用圆偏振放大替代线偏振放大以减少非线性相位积累，并且使用法拉第旋转镜自动抵消增益光纤中的双折射扰动，采用直接线性偏振输出避免在非保偏增益光纤中放大输出的偏振弱化效应。这一方案根本上解决了传输极限皮秒脉冲放大的问题。通过本项目对传输极限皮秒脉冲放大的深入研究，以期对皮秒量级脉冲的放大有一突破性的认识从而使对皮秒脉冲的利用可以赶上纳秒和飞秒脉冲。

中文关键词： 皮秒脉冲放大；光纤激光器；孤子动力学；耗散孤子共振；光纤放大器

英文摘要： Study on picosecond-pulse amplification is lagged behind that of femtosecond-/nanosecond-pulse amplification. Due to the narrow bandwidth of the picosecond pulses, there is no suitable method to amplify the pulse especially when the transform-limited pulse is required. However, high-energy picosecond pulses are needed for a variety of applications, such as micromachining. In the design of high peak power picosecond fiber amplifiers, it is crucial to avoid excessive nonlinear phase shift, which leads to spectral broadening and eventually to distortion of the temporal profile. The spectrum will broaden when the pulse propagates a distance longer than the nonlinear length. Ideally, the nonlinear length should exceed the length of the amplifier. To this end, one can decrease the peak power, and/or use gain fibers with large mode area. In this project, we study the dynamics of picosecond pulse amplification and propose a method to achieve transform-limited picosecond-pulse amplification. The key technique is the division of the seed pulse before the amplification and the recombination of the individual amplified pulses to obtain a pulse with high peak power. Apart from the using of large-mode-area gain fibers, circular polarization instead of linear polarization is considered in the amplification to reduce the accumu

英文关键词： picosecond pulse amplification；fiber lasers；soliton dynamics；dissipative soliton resonance；fiber amplifiers