1.9μm Tm激光抽运Ho：YAG激光器研究

发布时间：2018-01-10 01:12

本文关键词：1.9μm Tm激光抽运Ho：YAG激光器研究　出处：《长春理工大学》2015年硕士论文　论文类型：学位论文

更多相关文章： Tm:YLF 激光器 Ho:YAG 激光器 体光栅

【摘要】：2μm人眼安全激光处于大气窗口,可广泛应用于激光医疗、激光雷达、环境监测及光通信等领域;此外,2μm激光还可以作为3~5μm宽带可调谐中红外光参量振荡器的高效泵浦光。Ho:YAG晶体是产生高性能2μm激光的首选晶体之一,为了尽快获取高功率、高效率的2μm激光输出,本文开展了2.1μm Ho:YAG激光器及其泵浦源1.9μm Tm:YLF激光器的理论与实验研究。理论方面,首先根据Ho:YAG晶体的物理、机械及光谱特性,阐述了2.1μm Ho:YAG激光器的运转机制;然后依据Ho3+的跃迁机制,建立了考虑Ho-Ho上转换的准二能级速率方程模型,并依据此模型对激光器阈值、输出功率进行了求解;最后理论模拟并分析了上转换损耗、输出镜透过率、泵浦-激光模式比以及晶体参数对Ho:YAG激光器的影响,为后续激光器的设计与实验提供理论指导。实验方面,首先搭建了LD单端抽运Tm:YLF激光器,并依次研究了输出镜透过率、曲率半径及谐振腔长对输出特性的影响,以此选取了最佳的实验参数;其次,开展了以平面镀膜全反镜为腔镜的单LD双端抽运Tm:YLF激光器实验,获得了9.6W的1908nm激光输出,斜率效率和光光转换效率分别为35.9%和29%,线宽大于2nm,且输出波长随着注入功率增加从1908.2nm红移至1909.8nm;接着使用镀膜体光栅代替平面镀膜全反镜,实现了8.8W的1908.2nm激光输出,线宽仅为0.2nm,且波长红移不超过0.6nm。然后,开展了单程抽运Ho:YAG激光器实验,分别研究了输出镜透过率、曲率半径及谐振腔长对2.1μm激光输出特性的影响,在最佳输出条件下获得了4.6W的2122nm激光输出,线宽仅为0.2nm,斜率效率和光光转换效率分别为68.1%和53.2%;最后,根据实验结果分析,提出了高功率、高效率Ho:YAG激光器的设计方案。
[Abstract]:2 渭 m human eye safe laser is in the air window, which can be widely used in the fields of laser medical treatment, lidar, environmental monitoring and optical communication. In addition, the 2 渭 m laser can be used as the high efficiency pump light of 3 5 渭 m broadband tunable medium infrared parametric oscillator. How: YAG crystal is one of the preferred crystals to produce 2 渭 m laser with high performance. In order to obtain high power and high efficiency 2 渭 m laser output as soon as possible. In this paper, the theoretical and experimental studies of the 2.1 渭 m Ho:YAG laser and its pumping source of 1.9 渭 m Tm:YLF laser have been carried out. In theory, firstly, according to the physics of Ho:YAG crystal. Mechanical and spectral characteristics, the operating mechanism of 2.1 渭 m Ho:YAG laser is described. Then, according to the transition mechanism of Ho3, the quasi-two-level rate equation model considering Ho-Ho upconversion is established, and the threshold and output power of the laser are solved according to this model. Finally, the effects of up-conversion loss, output mirror transmittance, pump-laser mode ratio and crystal parameters on Ho:YAG laser are simulated and analyzed theoretically. It provides theoretical guidance for the design and experiment of the following laser. In the experimental aspect, the LD single-end pumped Tm:YLF laser is first built, and the transmittance of the output mirror is studied in turn. The influence of curvature radius and resonator length on the output characteristics is obtained, and the optimum experimental parameters are selected. Secondly, the experiment of single-LD double-end pumped Tm:YLF laser with planar coating mirror as mirror is carried out, and the output of 9.6W 1908nm laser is obtained. The slope efficiency and optical conversion efficiency are 35.9% and 29 respectively, the linewidth is larger than 2 nm, and the output wavelength shifts from 1908.2 nm to 1909.8 nm with the increase of injection power. Then, the thin body grating is used instead of the plane coating mirror, and the output of 1908.2 nm laser is realized. The line width is only 0.2 nm, and the wavelength red shift is not more than 0.6 nm. The experiment of single-pass pumped Ho:YAG laser is carried out. The effects of the transmittance of output mirror, the radius of curvature and the length of resonator on the output characteristics of 2.1 渭 m laser are studied. Under the optimum output conditions, the output of 4.6W 2122 nm laser is obtained. The linewidth is only 0.2 nm, the slope efficiency and optical conversion efficiency are 68.1% and 53.2 nm, respectively. Finally, according to the analysis of experimental results, the design scheme of high power and high efficiency Ho:YAG laser is proposed.
【学位授予单位】：长春理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN248

【共引文献】