共查询到20条相似文献,搜索用时 234 毫秒
1.
Numerical analysis and experimental results of output performance for Nd-doped double-clad fiber lasers 总被引:10,自引:0,他引:10
Nam Seong Kim Toshihiro Hamada Mahendra Prabhu Cheng Li Jie Song Ken-ichi Ueda Anping Liu Hong Jin Kong 《Optics Communications》2000,180(4-6):329-337
Numerical analysis is investigated for the high-power double-clad fiber lasers and experimental results using different microscope objectives for focusing into a Nd-doped rectangular double-clad fiber also performed. The numerical analysis includes dependence of output power on output mirror reflectivity, absorbed pump power, loss, and fiber length and pump power distribution for the cases of one-end and two-end pumps with 20 dB/km loss. Calculated conversion efficiencies are 76.36%, 69.73%, and 63.84% for lossless, two-end pump, and one-end pump fiber lasers, respectively. Slope efficiencies from absorbed pump power/output powers measured using microscope objectives are 16.8%/182 mW, 53.8%/351 mW, 24.9%/1240 mW, and 13.9%/649 mW for magnifications of 5×, 10×, 20×, and 40×, respectively. 相似文献
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An efficient shooting method for fiber amplifiers and lasers 总被引:1,自引:0,他引:1
Zohreh Lali-Dastjerdi Feisal Kroushavi Mohammad Hosein Rahmani 《Optics & Laser Technology》2008,40(8):1041-1046
A simple shooting method is proposed for the design of distributed multi-pumped Raman fiber amplifiers (RFAs) and Yb-doped double-clad fiber lasers (DCFLs). Using the proposed method a distributed RFA with 10 pump sources and 1700 mW total input pump power is simulated and high-power Yb-doped DCFL rate equations are solved numerically. The numerical simulation results show that the proposed method has good convergence in the condition of increasing numbers and power of input pump sources. 相似文献
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现在高功率光纤激光器和光纤放大器采用的双包层掺杂光纤,相对于从半导体泵浦激光器发射出的多模泵浦光束的大发散角,其内包层的直径很小,因此把泵浦光有效地耦合到双包层掺杂光纤的内包层是一个急需解决的难题。研制一种熔锥型侧面泵浦耦合器,可以大幅度提高泵浦光功率,实现增益光纤的多点泵浦,在双包层光纤放大器中使用良好,安全稳定,实现了较高的耦合效率,达到了70%,信号光通过率98%,信号输入与泵浦输入的隔离度大于50 dB,泵浦输入对输出端反向传输光的隔离度27 dB。通过对比结构紧凑性、耦合效率、系统稳定性等相关指标发现,熔锥型侧面泵浦耦合器完全可以满足高功率光纤激光器和光纤放大器的使用要求。 相似文献
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A theoretical modeling of Yb-doped double-clad fiber lasers under various pumping modes including arbitrary numbers of end-pump and side-pump is introduced. Approximate analytic expressions of distributed lasers along the whole fiber are derived, and their accuracies are investigated. The effect of the pumping mode on the output performance of fiber lasers is discussed. The numerical results show that the approximate analytic solution is in excellent agreement with the exact numerical solution of the rate equations, the output power in the side-pump scheme is lower than that in end-pumping scheme, and more uniform distributions of laser and pump powers can be achieved by adopting the distributed pump mode and optimizing the arrangement of pump powers. However, further flattening the pump distribution by using more pump points can degrade the laser efficiency. 相似文献
5.
Filippov V Chamorovskii Y Kerttula J Kholodkov A Okhotnikov OG 《Optics letters》2008,33(13):1416-1418
With a tapered double-clad all-glass ytterbium fiber as a gain medium, a maximum output power of over 200 W at 1079 nm and a slope efficiency of over 70% were demonstrated. The tapered double-clad fiber concept allows for using low-brightness diode bars and results in cost-effective and efficient high-power fiber lasers. The adiabatic conical fiber gain waveguide combines improved pump absorption owing to enhanced mode mixing in the pump cladding, low-noise single fundamental mode operation with M(2)< or =1.02, and strong potential for significant power scaling. 相似文献
6.
强泵浦下掺Yb3+双包层光纤激光器输出特性数值分析和实验研究 总被引:6,自引:0,他引:6
对强泵浦下线形腔掺Yb3+双包层光纤激光器输出特性进行了理论和实验研究。通过数值模拟,分析了泵浦光及激光在光纤中的分布、输出功率与泵浦功率的关系、光纤长度及腔镜反射率对激光输出功率的影响。在实验中,利用D型掺Yb3+双包层光纤获得了输出功率10 6W的光纤激光输出,斜率效率达86%。测量了在不同输出耦合条件下的输出功率、阈值泵浦功率和斜率效率,理论分析与实验结果基本一致,为进一步提高光纤激光器功率提供了理论和实验依据。 相似文献
7.
We present experimental demonstration of an end-pumping scheme based on splicing the multimode pump and single-mode signal fibers directly to a double-clad fiber with a tailored cross section. The method is used to pump a double-clad, erbium- and ytterbium-doped, fiber ring laser. The efficiency of the end-pumping method is tested by determining the slope efficiencies of the fiber ring laser and the fiber laser in a Fabry-Perot configuration. Comparable slope efficiencies are found when both laser configurations have similar output coupler ratios. The developed pumping scheme and double-clad fiber can find applications in cost-effective power fiber amplifiers and lasers. 相似文献
8.
High-power and wavelength-tunable operation of an Er,Yb fiber laser using a volume Bragg grating 总被引:2,自引:0,他引:2
Efficient high-power operation of double-clad Er,Yb-doped fiber lasers with fixed-wavelength and wavelength-tunable resonator configurations using volume Bragg gratings for wavelength selection are reported. The fixed-wavelength laser yielded a maximum output power of 103 W at 1552.6 nm with a linewidth of ~0.4 nm (FWHM) for a launched pump power of 290 W at 976 nm. The wavelength-tunable laser could be tuned from 1528 to 1550 nm with a linewidth of 0.2 nm (FWHM) and with output power in the range 30-38 W for a launched pump power of 120 W. The prospects for further improvement in performance are considered. 相似文献
9.
Efficient single-mode operation of a cladding-pumped ytterbium-doped helical-core fiber laser 总被引:3,自引:0,他引:3
A novel approach to achieving robust single-spatial-mode operation of cladding-pumped fiber lasers with multimode cores is reported. The approach is based on the use of a fiber geometry in which the core has a helical trajectory within the inner cladding to suppress laser oscillation on higher-order modes. In a preliminary proof-of-principle study, efficient single-mode operation of a cladding-pumped ytterbium-doped helical-core fiber laser with a 30 microm diameter core and a numerical aperture of 0.087 has been demonstrated. The laser yielded 60.4 W of output at 1043 nm in a beam with M2 < 1.4 for 92.6 W launched pump power from a diode stack at 976 nm. The slope efficiency at pump powers well above threshold was approximately 84%, which compares favorably with the slope efficiencies achievable with conventional straight-core Yb-doped double-clad fiber lasers. 相似文献
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将双凹槽金属二元光栅用于侧面泵浦大功率双包层光纤激光器中,这种具有等槽深、不等线宽的双凹槽金属二元光栅可以被直接制作在双包层光纤的侧面内包层上,以实现大功率的激光泵浦。通过选择梯度优化算法(如拟牛顿算法)和微型遗传算法准确地预测出:利用这种双凹槽金属二元光栅结构能实现对TE偏振光的耦合效率为77.27%,而对TM偏振光的耦合效率为94.77%。同时,也对这种结构的制作容差和最小特征尺寸进行了分析和计算。 相似文献
12.
An output power of 1.74 W at 2.03 microm was generated at a slope efficiency of 51% when a double-clad Tm(3+)-doped silica fiber laser was pumped with high-power 1150 nm diode lasers. Pump excited state absorption from the upper laser level populates higher energy levels allowing cross relaxation to repopulate the upper laser level at a quantum efficiency greater than unity and to limit losses relating to additional pump excited state absorption. The output power was scaled to 4.77 W when both ends of the fiber were pumped. 相似文献
13.
侧面耦合高功率泵浦光技术是获得高功率稀土光纤激光器的关键技术之一。介绍了一种用于侧面泵浦高功率双包层光纤激光器的表面弧形金属槽结构的制作工艺,并且针对已经实验制作出来的表面连续弧形金属凹槽的侧面耦合结构进行了严格的矢量电磁场理论计算,将120°弧形凹槽等效近似为多层等高不等宽的矩形槽并运用透射矩阵算法对这种近似后的多层矩形结构进行优化设计。这种结构可以用于大功率激光二极管阵列的侧面泵浦中,尤其可用于条形半导体激光器侧面泵浦双包层掺杂光纤,以制作各种大功率稀土光纤激光器。 相似文献
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A novel shooting method with excellent simple control strategy is developed for solving the failure to convergence of the traditional shooting methods themselves in fiber lasers model. Compared with the published literature, the novel shooting method provides a clear physical understanding method for getting the threshold pump power and the exact results with given random functions in Yb3+-doped fiber lasers and Er3+-doped fiber lasers. Then, the results in Er3+-doped fiber lasers and Yb3+-doped fiber lasers demonstrate that the solutions using the novel shooting method has high accuracy of 10−8 W with several iteration steps, which have extended the applicable range of the end-pumped power even lower than 1 mW pump power. Furthermore, compared with 1480 nm pump for the threshold and slope efficiencies of the Er3+-doped fiber lasers, 978 nm fiber lasers can extend wider scope of application and be pump source in the coming future. Finally, the lower threshold and higher slope efficiency at 975 nm than those of 910 nm pump in Yb3+-doped fiber lasers, 975 nm pump laser provides for broad band excellent cladding pump source. 相似文献
17.
An approximate analytic solution of strongly pumped Yb-doped double-clad fiber lasers without neglecting the scattering loss 总被引:6,自引:0,他引:6
A theoretical analysis of strongly pumped Yb-doped double-clad fiber lasers is presented and an approximate analytic function of distributed laser along the whole fiber with the scattering loss is obtained for the first time. A comparison is made between the analytic solution and the exact numerical solution. The results have shown that the analytic function of distributed laser within the fiber is accurate and explicit. With the analytic solution the losses caused by laser scattering are shown in three different pump modes. The results verify that the backward pumping can get the highest output power in strongly pumped fiber lasers. 相似文献
18.
A highly efficient double-clad Yb3+-doped fiber laser with a novel cladding geometry is described. A round double-clad fiber with a small D-shaped hole for breaking a circular symmetry in a cladding combines the advantages of ease of manufacture and handling round fibers with efficient absorption of pump light. Fiber lasers with a double-D cladding shape and a D-hole cladding are compared. We report what are to our knowledge the highest slope efficiencies of 73% and 69%, respectively, pumping at 915 nm. Output powers in excess of 13 W are demonstrated. 相似文献
19.
采用国产大模场面积双包层光纤的714W连续光纤激光器 总被引:33,自引:2,他引:31
采用两个中心波长约976 nm准直输出的高功率半导体激光模块为抽运源,通过空间滤波和非球面透镜耦合技术,双端抽运长度为21 m的大模场面积国产掺镱双包层光纤,获得了714.5 W的高功率连续激光输出。采用反向抽运,当入纤抽运功率为760 W时,激光输出功率达到501 W;采用双端抽运,当入纤抽运功率为1137 W时,获得了714.5 W的高功率连续输出,光光转换效率为62.8%,斜率效率为67%。 相似文献
20.
Zhang Fan Wang Chun-can Ning Tigang Liu Chu Geng Rui Lu Yuchun 《Optics Communications》2009,282(16):3325-2143
A multi-point side pumping scheme of double-clad fiber lasers was presented for high-power diode arrays. It made use of multiple dielectric transmission gratings to realize high coupling efficiency and low pump light leakage ratio simultaneously. Appropriate material and practical structural parameters of the transmission gratings were chosen and designed by using a rigorous Eigen-mode theory combined with a genetic algorithm (GA) and a quasi-Newton method. The GA provided initial parameter values for the quasi-Newton method to get the final optimal results. For TE-polarized pump lights, a perfect transmission grating structure was found for side pumping and the coupling efficiency (CE) of 98% can be achieved. Meanwhile, the CE is 83% for TM-polarized pump lights. And the leakage ratios of the pump lights were only 11.3% and 4.9% for TE- and TM-polarized when a multi-point side pumping scheme was adopted. 相似文献