基于腔内泵浦双波长激光器的研究

发布时间：2018-04-03 21:16

本文选题：双波长激光器　切入点：腔内泵浦　出处：《长春理工大学》2017年硕士论文

【摘要】：如今,双波长激光固体激光器在各种领域有着十分广泛的应用,比如激光通讯、激光医疗、光谱分析、激光雷达、非线性混频等等。但是现在大部分双波长激光输出只由单一晶体实现双波长激光跃迁,由于跃迁谱线的发射截面之间存在差异,使得激射的两波长之间存在着激烈的增益竞争,所以很难获得高效稳定的双波长激光输出。本论文针对这一问题,提出了腔内泵浦技术来实现双波长同时输出的技术方案,并开展了相关的理论分析和实验研究。1.通过腔内泵浦运转机理对其中涉及到的间接泵浦理论、直接泵浦理论、以及准三能级、四能级激光理论进行分析,建立了能够描述腔内泵浦双波长激光器振荡机理和输出特性的理论模型,在此基础上对输出镜的透过率进行了优化设计。2.运用ABCD矩阵模拟了腔内泵浦双波长激光传输过程,在此基础上通过仿真模拟理论进行了腔内泵浦双波长激光器的谐振腔设计,得到了相应的谐振腔稳区,并确定了能实现热稳腔的腔镜参数。在此基础上对腔内束腰大小以及位置进行了模拟,为实验奠定了理论基础。3.通过上述腔内泵浦双波长激光器的理论模拟开展了实验研究:(1)通过Nd:YAG和Nd:YVO4激光增益介质来实现高效率的946nm和1064nm激光输出。采用808nm间接泵浦作为泵浦源,在泵浦功率为30.5W时,获得4W的双波长输出,此时946nm和1064nm双波长激光输出功率分别为1.1W和2.9W。并且在实验中,通过调节四能级激光增益介质的位置实现了1064nm激光1.0W—2.9W输出功率可调节。(2)随后对泵浦源更换为879nm激光泵浦源,并开展了直接泵浦腔内泵浦实验。应用Nd:GdVO4和Nd:YVO4激光增益介质来实现912nm和1064nm双波长激光输出,此种泵浦方式可以有效的缓解激光器的热效应,通过对国内外论文的调研得知,这种采用直接泵浦形式实现腔内泵浦双波长的输出为国内首例。在实验中,泵浦吸收功率为8.55W时,获得1.65W的双波长输出,此时912nm和1064nm双波长激光输出功率分别为0.58W和1.07W。
[Abstract]:Nowadays, dual-wavelength laser solid-state lasers are widely used in various fields, such as laser communication, laser medical treatment, spectral analysis, lidar, nonlinear mixing and so on.However, most of the double wavelength laser output is only realized by a single crystal. Due to the difference between the emission cross sections of the transition lines, there is a fierce gain competition between the two wavelengths of the stimulated laser.Therefore, it is difficult to obtain high efficient and stable double wavelength laser output.In order to solve this problem, an intracavity pumping technique is proposed to realize the simultaneous output of two wavelengths, and the related theoretical analysis and experimental research are carried out.The indirect pump theory, direct pump theory and quasi-three-level, four-level laser theory are analyzed by the mechanism of intracavity pumping operation.A theoretical model which can describe the oscillation mechanism and output characteristics of intracavity pumped dual-wavelength laser is established, and the transmittance of the output mirror is optimized. 2.The ABCD matrix is used to simulate the propagation process of intracavity pumped dual-wavelength laser. Based on the simulation theory, the cavity design of the intracavity pumped dual-wavelength laser is carried out, and the corresponding cavity stability region is obtained.The parameters of the cavity cavity are determined.On this basis, the size and position of the beam waist in the cavity are simulated, which lays a theoretical foundation for the experiment.Through the theoretical simulation of the intracavity pumped dual-wavelength laser, the experimental study was carried out. The Nd:YAG and Nd:YVO4 laser gain media were used to realize the high efficiency 946nm and 1064nm laser output.When the pump power is 30.5 W, the output power of 946nm and 1064nm is 1.1 W and 2.9 W, respectively.In the experiment, the 1064nm laser 1.0W-2.9W output power can be adjusted by adjusting the position of the four-level laser gain medium. Then the pump source is replaced by the 879nm laser pump source, and the direct pump intracavity pumping experiment is carried out.Using the gain medium of Nd:GdVO4 and Nd:YVO4 laser to realize the double wavelength laser output of 912nm and 1064nm, this kind of pumping method can effectively alleviate the thermal effect of laser.It is the first case in our country that the double wavelength output of intracavity pump is realized by direct pumping.In the experiment, when the pump absorption power is 8.55W, the two-wavelength output of 1.65W is obtained, and the output power of 912nm and 1064nm dual-wavelength laser is 0.58W and 1.07W, respectively.
【学位授予单位】：长春理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN248

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