高功率连续波掺镱光纤激光器研究进展

党文佳; 李哲; 李玉婷; 卢娜; 张蕾; 田晓; 杨慧慧

doi:10.37188/CO.2019-0208

高功率连续波掺镱光纤激光器研究进展

doi: 10.37188/CO.2019-0208

党文佳^1, ,,
李哲²,
李玉婷¹,
卢娜¹,
张蕾¹,
田晓¹,
杨慧慧¹

1.
西安航空学院理学院，陕西西安 710077
2.
中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室，陕西西安 710119

基金项目: 国家自然科学青年基金项目(No.11804264)；陕西省自然科学基础研究计划资助项目(No.2019JQ-914)；陕西省创新能力支撑计划项目(No.2019KRM093)；陕西省教育厅专项科研计划项目(No.17JK0394、No.19JK0429)

详细信息

作者简介:
党文佳（1983—），女，博士，讲师，陕西西安人，2015年于西安电子科技大学获得工学博士学位，主要从事光外差探测、光纤激光器及光电子技术方面的研究。E-mail：wenjia_dang@126.com

中图分类号: O436
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出版历程
- 收稿日期: 2019-10-24
- 修回日期: 2019-11-21
- 刊出日期: 2020-08-01

Recent advances in high-power continuous-wave ytterbium-doped fiber lasers

1.
School of Science, Xi’an Aeronautical University, Xi’an 710077, China
2.
State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China

Funds: Supported by the National Natural Science Foundation of China (No.11804264); Natural Science Basic Research Program of Shaanxi (No.2019JQ-914); Innovation Capability Support Program of Shaanxi (N0.2019KRM093); Scientific Research Program Funded by Shaanxi Provincial Education Department (No.17JK0394; No.19JK0429)

More Information

Corresponding author: wenjia_dang@126.com

摘要

摘要: 高功率连续波掺镱光纤激光器因具有电光效率高、光束质量好、热管理方便等优点，在工业加工、军事国防、科学研究等领域得到广泛应用，但是高功率条件下的非线性效应和热效应限制了其输出功率的进一步提升。基于此，本文重点分析了受激拉曼散射非线性效应和热致模式不稳定现象的形成机理和抑制方法，为高功率光纤激光系统的设计与集成提供了参考，并详细介绍了2015年以来为克服两种因素的影响所取得的最新研究成果，最后展望了高功率连续波掺镱光纤激光器的发展趋势。
- 高功率光纤激光器 /
- 主振荡功率放大器 /
- 受激拉曼散射 /
- 模式不稳定
Abstract: High power continuous-wave ytterbium-doped fiber lasers have unique advantages such as high electro-optical efficiency, excellent beam quality and good thermal management. For these reasons, these fiber lasers are widely used in industrial processing, national defense and military, and scientific research. However, their non-linear and thermal effects at high-power conditions limit the further improvement of their output power. In this paper, the formation mechanism and corresponding suppression methods of stimulated raman scattering and thermally induced mode instability are analyzed. We hope that these analyses can provide some reference for the design and integration of high-power fiber laser systems. The research results for overcoming these limited factors introduced since 2015 are then discussed in detail. This paper is concluded by predicting the development prospects of high-power continuous-wave ytterbium-doped fiber lasers.
- high power fiber laser /
- master oscillator power amplifier /
- stimulated raman scattering /
- mode instability

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图 1 硅基光纤的拉曼增益谱^[20]

Figure 1. Raman gain spectrum of silica fibers^[20]

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图 2 热致折射率光栅的物理机制^[42]

Figure 2. Physical mechanism of thermally induced grating^[42]

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图 3 5 kW全光纤单模光纤激光器的示意图^[51]

Figure 3. Schematic diagram of 5 kW all-fiber single mode fiber laser^[51]

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图 4 5 kW全光纤激光器输出特性。（a）输出功率与光束质量；（b）输出光谱^[51]

Figure 4. Output performance of 5 kW single mode all-fiber oscillator. (a) Output power and beam quality; (b) output spectrum of 5 kW fiber laser^[51]

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图 5 （a）MOPA结构全光纤激光器结构示意图；（b）全光纤激光振荡器结构示意图^[52]

Figure 5. (a) Schematical setup of the monolithic fiber amplifier; (b) schematical setup of the fiber oscillator^[52]

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图 6 （a）全光纤激光振荡器效率；（b）全光纤激光振荡器光谱随功率变化^[52]

Figure 6. (a) Efficiency of the fiber oscillator; (b) spectral evolution of the fiber oscillator with increasing power^[52]

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图 7 全光纤激光振荡器实验结构^[56]

Figure 7. Experimental setup of the monolithic fiber laser oscillator^[56]

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图 8 （a）输出功率及其斜率效率；（b）输出光谱；（c）5.2 kW的时域信号及其傅立叶光谱^[56]

Figure 8. (a) Output power and corresponding optical effciency at different pump powers; (b) optical spectrum of the output laser; (c) time domain signal and its Fourier spectrum at an output power of 5.2 kW^[56]

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图 9 全光纤激光振荡器实验结构^[58]

Figure 9. Experimental setup of the monolithic fiber laser oscillator^[58]

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图 10 （a）全光纤激光振荡器的斜率效率；（b）不同功率时的输出光谱^[58]

Figure 10. (a) Slope efficiency of the monolithic fiber laser oscillator; (b) optical spectra at different output powers^[58]

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图 11 （a）增益光纤与传输光纤的折射率分布；（b）激光器功率及斜率效率；（c）光束质量^[59]

Figure 11. (a) Refractive index profiles of a matched passive-active fiber couple; (b) slope efficiency of the laser power; (c) corresponding beam M² measurement^[59]

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图 12 全光纤激光器和输出特性测试系统示意图^[60]

Figure 12. Schematic diagram of the all-fiber-integrated fiber laser and the measuring system

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图 13 级联泵浦光纤激光器中抑制SRS的实验结构示意图^[62]

Figure 13. Schematic of experimental configuration for the suppression of SRS in a tandem pumping fiber amplifier^[62]

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图 14 输出光谱随泵浦功率的变化。（a）不使用CTFBG；（b）使用一个CTFBG；（c）使用两个CTFBG^[62]

Figure 14. Changing spectra of output as the pump power increases (a) without and (b) with a CTFBG and (c) with two CTFBGs inserted^[62]

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图 15 （a）在合适的种子功率注入条件下的全光纤放大器斜率效率；（b）全光纤放大器在最大输出功率时的输出光谱^[63]

Figure 15. (a) Slope efficiency of the all-fiber amplifier with a suitable seed power injected; (b) spectra of the all-fiber amplifier signal beam at the maximum output power^[63]

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图 16 用于增益光纤性能测试的MOPA光纤激光系统^[65]

Figure 16. MOPA configuration for fiber performance test^[65]

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图 17 （a）Yb/Ce共掺光纤放大器的输出功率随泵浦功率的变化；（b）增益光纤在4.62 kW时的热像图；（c）激光光谱^[65]

Figure 17. (a) Output power of the Yb/Ce co-doped fiber power amplifier varying with the increase of pump power; (b) thermal image of the active fiber at 4.62 kW; (c) laser spectrum^[65]

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图 18 (3+1)型GT-Wave光纤结构示意图。（a）横截面；（b）侧面视图^[66]

Figure 18. Schematic diagram of (3+1) GT-Wave fiber. (a) Cross-section; (b) side-view^[66]

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图 19 (8+1)型GT-wave光纤激光放大器实验系统^[67]

Figure 19. Experimental setup of (8+1) GT-Wave fiber amplifier system^[67]

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图 20 (8+1)型GT-wave光纤激光放大器输出功率和输出光谱^[67]

Figure 20. Laser output power and output spectrum of (8+1) GT-Wave fiber^[67]

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图 21 6 kW双向泵浦的MOPA结构全光纤激光器结构示意图^[69]

Figure 21. Schematic of all-fiber 6 kW bidirectional pumping MOPA laser^[69]

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图 22 （a）系统输出功率随泵浦功率的变化；（b）光纤放大器的输出出光谱^[69]

Figure 22. (a) Output power of the system versus the total pumping power; (b) spectrum of output laser from the fiber laser amplifier^[69]

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图 23 （a）5 kW和（b）8 kW连续波全光纤激光器结构示意图^[70]

Figure 23. Schematic configurations of the 5 kW (a) and 8 kW (b) CW monolithic fiber laser^[70]

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图 24 （a）5 kW光纤激光器输出功率；（b）5 kW光纤激光器输出光谱；（c）8 kW光纤激光器输出功率；（d）8 kW光纤激光器输出光谱^[70]

Figure 24. (a) Output power of the 5 kW fiber laser; (b) output spectrum of the 5 kW fiber laser; (c) output power of the 8 kW fiber laser; (d) output spectrum of the 8 kW fiber laser^[70]

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图 25 激光实验装置示意图^[71]

Figure 25. Experimental setup of the laser system^[71]

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图 26 （a）激光功率和斜率效率曲线；（b）不同功率光谱测试结果^[71]

Figure 26. (a) Experimentally measured laser power and slope efficiency; (b) test results of spectra of different output laser powers^[71]

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表 1 高功率连续波掺镱光纤激光器研究进展

Table 1. Recent advances in high power continuous-wave ytterbium-doped fiber lasers

Type of fiber laser	Year	Institution	Power	Active fiber parameter	Pumping method
Monolithic fiber laser oscillator	2016	Fujikura, Japan	2 kW	A_eff=400μm², NA=0.07	915 nm bi-pump
	2016	NUDT, China	2 kW	D_core=21μm, NA=0.066	915 nm and 976 nm co-pump
	2016	NUDT, China	2.5 kW	D_core=20μm, NA=0.065	976 nm bi-pump
	2017	NUDT, China	1.969 kW	D_core=25μm, NA=0.09	976 nm bi-pump
	2017	NUDT, China	3.05 kW	D_core=20μm, NA=0.065	976 nm bi-pump
	2017	Fujikura, Japan	3 kW	A_eff=400μm², NA=0.07	915 nm bi-pump
	2018	NUDT, China	3.96 kW	D_core=25μm, NA=0.065	915 nm bi-pump
	2018	Fujikura, Japan	5 kW	A_eff=600μm²	976 nm bi-pump
	2018	Jena, Germany	5 kW	D_core=20μm, NA=0.06	976 nm bi-pump
	2018	NUDT, China	5.2 kW	D_core=25μm, NA=0.065	915 nm bi-pump
MOPA monolithic fiber laser	2015	NUDT, China	2.14 kW	D_core=30μm, NA=0.06	1018 nm co-pump
	2015	NUDT, China	3.15 kW	D_core=30μm	915 nm co-pump
	2016	HUST, China	3 kW	D_core=25μm, NA=0.06	976 nm bi-pump
	2016	XIOPM, China	3.5 kW	D_core=30μm, NA < 0.062	976 nm co-pump
	2016	Jena, Germany	4.3 kW	D_core=22μm, NA < 0.04	976 nm counter-pump
	2016	CAEP, China	5.07 kW	D_core=30μm, NA=0.066	976 nm bi-pump
	2017	XIOPM, China	4.62 kW	D_core=30μm, NA=0.06	976 nm co-pump
	2017	Tsinghua, China	3.12 kW	D_core=25μm, NA=0.06	976 nm bi-pump
	2017	TJU, Chia	8.05 kW	D_core=50μm, NA=0.06	976 nm co-pump
	2018	Tsinghua, China	6.02 kW	D_core=25μm, NA=0.06	976 nm bi-pump
	2018	CAEP, China	11.23 kW	D_core=30μm, NA=0.064	976 nm bi-pump
	2019	NUDT, China	4.2 kW	D_core=30μm	976 nm co-pump
	2019	SIOM, China	10.14 kW	D_core=30μm, NA=0.06	976 nm bi-pump

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