高功率脉冲(10 MW)激光光纤偏振走离复合放大技术

项目名称： 高功率脉冲(10 MW)激光光纤偏振走离复合放大技术

项目编号： No.61475081

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 无线电电子学、电信技术

项目作者： 张海涛

作者单位： 清华大学

项目金额： 82万元

中文摘要： 提出光纤偏振走离复合放大技术，以突破脉冲光纤激光所受到的自聚焦、受激 拉曼、布里渊散射、自相位调制等材料非线性效应对高峰值功率的瓶颈限制，展开10MW 级 皮秒脉冲高峰值功率脉冲光纤激光的理论和实验研究。首先研究高双折射空芯光子带隙光纤 结构与模式特性，建立适合高功率10ps 级短时间间隔的偏振分离脉冲序列在空芯光纤、大 模场光纤传输与放大过程的物理模型，从而能够探求模式色散、光谱色散、波形畸变、模式 畸变等激光输出特性在不同光纤参数、泵浦参数、以及非线性效应等条件下的理论规律；结 合理论研究结果设计实验方案，研制出低损耗光纤偏振走离复合光纤系列，与高功率空芯光 纤环形器、大模场法拉第旋转镜、大模场泵浦合束器等新型器件，拟获得波长1.03μm，脉 宽约10ps，脉冲重复频率50kHz，超过石英光纤自聚焦阈值的10MW 脉冲峰值功率、近衍射 极限光束质量的光纤激光输出。

中文关键词： 10MW峰值功率；高功率光纤激光器；光纤偏振走离合成放大；高双折射空芯光纤；高功率空芯光纤环行器

英文摘要： We present a fiber pulse polarization division combing amplification technique to break through the limitation on the maximum pulse peak power set by fiber nonlinear effects, e.g., self-focus, Stimulated Raman and Brillouin Scattering, self-phase-modulation. We study the theory and experiment of the fiber pulse laser at 10 MW high peak power output. Firstly, an analytic model is developed to design the high birefringence hollow core photonic bandgap fiber structure and evaluate its mode distribution and transmission. We build the physical mode of the fiber transmission and amplification progress of the fiber polarization division combining pulse trains at 10-ps order short pulse spacing. We achieve the influence rule of the fiber parameters, pump parameters and nonlinear effects of the mode dispersion, spectrum dispersion, pulse shape distortion and mode distortion. We do research the key elements of system, including low loss polarization division combining fiber series, high power hollow core fiber circulator, large mode field fiber Faraday rotator mirror and pump combiner. Finally, a peak power of greater than 10 MW and over the silica fiber self focus limitation with a diffracted limitation beam quality, ~10ps pulse duration, wavelength of 1.03μm, 50 kHz repetition rate will be developed experimentallly.4

英文关键词： 10-MW peak power;High power fiber laser;Fiber polarization division combining amplification;High birefringence hollow core fiber;High power hollow core fiber circular