共查询到20条相似文献,搜索用时 31 毫秒
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S. Wang X. Wang F. Kallmeyer J. Chen H.J. Eichler 《Applied physics. B, Lasers and optics》2008,92(1):43-48
The laser resonator structure and beam diameter change with the pump power due to the thermal lens effect. This influences
the output power. With increasing pump power, the output power sharply decreases when the cavity becomes unstable. In order
to describe this situation, rate equations considering the cavity structure and the thermal lens effect are presented; numerical
methods are used to solve them. This modeling can be used in repetitively pulsed laser systems when the thermal lens depends
on the average pump power, while the peak value of the output power and pump power are considered by the rate equations. Experiments
are performed with 50 Hz LD diode pumped Nd:GSAG laser crystal operating at the quasi-three-level laser transition with 942 nm
wavelength. Fitting the calculated results to experimental data allows to determine the cavity loss.
PACS 42.55.Xi; 42.60.Da 相似文献
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A. D. Lyashedko V. F. Seregin V. B. Tsvetkov I. A. Shcherbakov 《Bulletin of the Lebedev Physics Institute》2010,37(11):335-339
Generation characteristics of the neodymium laser with disk active element and diodepumped active medium were studied. It
was shown that lasing occurs at a cavity length significantly exceeding the focal length of the thermal lens induced in the
active element. Bending radii of the active disk surface were determined depending on the absorbed pump power. The cavity
calculation performed taking into account the active disk surface bending showed that the negative lens formed by such bending
of the surface and a laser mirror deposited on it efficiently compensates for the positive thermal lens, thus expanding the
stability region of the disk laser cavity. 相似文献
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Y. F. Ma X. Yu X. D. Li J. Gao J. B. Peng F. Chen Z. Zhang J. H. Yu 《Laser Physics》2008,18(12):1505-1507
A planoconvex cavity is used to compensate the thermal lens effectively for a Q-switched Nd:GdVO4 laser. The good beam quality of the continuous-wave (CW) output laser was obtained and the performances of the Q-switched laser were improved remarkably. The pulse width reduced and the output ratio of the Q-switching to free running increased resulting from the good beam quality of the planoconvex cavity compared with those used on a flat-flat cavity. 相似文献
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In order to solve the hard problem of laser instability, an electro-optically Q-switched Ce:Nd:YAG laser by using the optimized
concavo-convex cavity is demonstrated. The laser with the optimized cavity is insensitive to the thermal lens of laser crystal
and has excellent stability of average output pulse energy and threshold voltage under different environment temperature of
−45, 25, and 55°C. 相似文献
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高光束质量、高功率稳定性激光器在激光加工、激光测量等领域具有广泛的用途.为了实现激光器腔内光斑聚焦同时减少色散和体积,人们常常将曲面反射镜用在激光谐振腔中,但光束倾斜入射到曲面反射镜往往会引起像散,从而导致光斑质量恶化,并降低激光器的性能.另一方面,在高功率激光器或超短脉冲激光器中,激光增益介质热透镜焦距的起伏,是导致激光输出功率波动的主要原因之一.针对激光器的像散和功率波动这两个问题,本文提出了一套简单高效的解决方案,在考虑像散补偿和热透镜效应的基础上,基于传播变换圆理论,首次提出一种可实现高光束质量、高功率稳定性激光器谐振腔的设计方法,并对采用该方法所设计出的超短脉冲激光器进行理论与实验研究.研究结果表明,利用该方法设计的激光谐振腔,两端臂像散能够完全被补偿,实验上实现了基模高斯光束输出;当激光晶体热透镜焦距改变时,该方法所设计出的激光谐振腔内各关键位置光斑半径的变化,显著地小于普通谐振腔,在相同外界条件下,其输出激光功率稳定性明显优于普通激光器. 相似文献
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In order to solve the hard problem of laser instability, a miniature Cr4+:YAG Q-switched Ce:Nd:YAG laser with a retroreflecting corner cube prism is demonstrated. The corner cube prism is insensitive
to misalignment in any direction. Laser cavity with the prism is found to meet the condition of violent change of environment
temperature and the variation of thermal lens of laser crystal by our experiment. Compared with flat-flat cavity, stability
of the laser with a retroreflecting corner cube prism is improved remarkably. 相似文献
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We study a Cr4+:YAG Q-switched Nd:YAG laser with a thermally-insensitive corner-cube-prism cavity where the corner cube prism is the key element. The corner cube prism is insensitive to misalignment in any direction. We demonstrate experimentally that a laser cavity with such a prism provides stable laser performance under violent changes of ambient temperature and the effect of the laser crystal thermal lens. The laser mode properties are analyzed by numerical simulations. We show that the numerically simulated results agree well with the experimental ones. 相似文献
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We demonstrate that the simultaneous self-mode-locking of TEM0,0 and TEM1,0 modes can be achieved in a standard end-pumped Nd:YVO4 laser. With this simultaneous self-mode-locking, the transverse beat frequency can be accurately measured as a function of
the absorbed power. We employ the measured beat frequency and the cavity theory to precisely determine the effective focal
length of the thermal lens in the gain medium. 相似文献
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为了获得大功率高亮度的激光光源,设计并实现了一种使用双棒串接的基模动态稳定谐振腔.通过补偿热致双折射效应以及合理地设计腔内参数,在使用闪光灯抽运的条件下获得了61W的基模连续输出.使用等效热透镜的方法分析了谐振腔参数对激光器性能的影响,解释了输出镜和全反镜的距离对激光器性能所起的不同作用.
关键词:
动态稳定腔
双棒
谐振腔模式 相似文献
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端面泵浦双Nd: YVO4激光器中热效应对腔稳定性的影响 总被引:7,自引:6,他引:1
利用多个激光晶体串接方式可以提高固体激光器的输出功率. 发展双Nd: YVO4晶体激光器, 将晶体的端面镀膜作为谐振腔的端面镜, 构成了平行平面谐振腔. 对平行平面谐振腔的等效腔进行了理论分析, 结果表明激光晶体吸收泵浦光产生的热透镜效应对保持腔的稳定性起到了重要的作用. 在国内首次进行了双端泵浦双Nd: YVO4激光器的实验研究, 在抽运功率为 20.74 W时获得了11 W的1064 nm TEM00模激光输出, 其光-光转化效率约为53%. 并且对于不同掺杂浓度下的实验结果进行了讨论. 相似文献
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利用与铯原子吸收线对应的852 nm半导体激光作为基频光,泵浦基于周期极化磷酸钛氧钾(PPKTP)晶体的环形腔,进行高效外腔谐振倍频并产生426 nm激光.在理论分析小角度环形腔内的热透镜效应基础上,发现晶体中等效热透镜中心位置并非在晶体的几何中心.在理论分析的基础上,实验上通过精密平移台精细调节PPKTP晶体在腔内位置,使得等效热透镜中心位置与谐振腔的腰斑位置重合,进而减小晶体热透镜效应导致的模式失配对倍频效率的影响.在泵浦功率为515 mW时产生了428 mW的426 nm激光输出,对应的倍频转换效率为83.1%.此高效倍频过程为制备与铯原子吸收线相匹配的非经典光场提供有效泵浦光,为推动量子非经典光场的应用以及量子信息科学的发展奠定基础. 相似文献
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为构建LD泵浦Nd∶GdVO4/KTP腔内倍频热效应不敏感的激光器系统,提高绿光激光的热稳定性,利用基于传播圆变换理论的Z型腔图解分析方法,得到光斑半径w2、w3随热动力参数1/ft的变换关系,利用Mathematics编程软件计算得到了具有激光晶体热透镜不敏性的Z型折叠腔参数。当激光器腔长参数为170mm, 523mm和152mm时,在20.3W的注入泵浦功率下获得了2.72W的531.5nm连续绿光激光输出,实现光 光转换率13%。通过传播圆变换理论图解分析方法的理论计算和实验研究,发现在1/ft小于0.25cm-1的情况下,该腔在激光晶体和倍频晶体处的光斑大小稳定,热效应不敏感,像散不明显。 相似文献
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The paper reports on the characterization of a side-pumped 40 W CW Nd:YAG laser. A side-pumping configuration with six laser diodes is used for the laser. We show the comparison between the calculated and measured pump energy distributions in the laser crystal. The birefringence and the thermal lens effect of the Nd:YAG crystal have been experimentally investigated, and their influence on the performance of the laser are discussed. Output power and beam quality of the laser under different output couplings, cavity lengths, types of cavity and different temperatures of the cooling water have been experimentally studied. 相似文献
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Thermal effect control is critical to scale the output power of diode end-pumping solid lasers to several watts up and beyond. Diffusion bonding crystal has been demonstrated to be an effective method to relieve the thermal lens for the end-pumping laser crystal. The temperature distribution and thermal lens in Nd:YVO4/YVO4 composite crystal was numerically analyzed and compared with that of Nd:YVO4 crystal in this paper. The end-pumping Nd:YVO4/YVO4 composite crystal laser was set up and tested with z cavity. The maximum output power of 9.87 W at 1064 nm and 6.14 W at 532 nm were obtained at the pumping power of 16.5 W. The highest optical-optical conversion efficiencies were up to 60% at 1064 nm and 40% at 532 nm, respectively. 相似文献