大规模激光相干合成主动相位控制技术研究进展

周宏冰; 张昊宇; 李敏; 冯曦; 谢亮华; 刘玙; 楚秋慧; 闫玥芳; 陶汝茂; 林宏奂; 王建军; 颜立新; 景峰

doi:10.11884/HPLPB202436.230426

大规模激光相干合成主动相位控制技术研究进展

doi: 10.11884/HPLPB202436.230426

周宏冰^{1, 2,},
张昊宇¹,
李敏¹,
冯曦¹,
谢亮华¹,
刘玙¹,
楚秋慧¹,
闫玥芳¹,
陶汝茂^1, ,,
林宏奂¹,
王建军¹,
颜立新²,
景峰¹

1.
中国工程物理研究院激光聚变研究中心，四川绵阳 621900
2.
清华大学加速器实验室，北京 100084

基金项目: 国家自然科学基金项目(62205317)

详细信息

作者简介:
周宏冰 zhouhb21@mails.tsinghua.edu.cn

通讯作者:
陶汝茂 supertaozhi@163.com。

中图分类号: O436
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- 文章访问数: 110
- HTML全文浏览量: 30
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- 被引次数: 0
出版历程
- 收稿日期: 2023-12-01
- 修回日期: 2024-03-11
- 录用日期: 2024-03-11
- 网络出版日期: 2024-03-25
- 刊出日期: 2024-05-11

Progress in active phase control for large-scale coherent laser beam combining

1.
Laser Fusion Research Center, CAEP, Mianyang 621900, China
2.
Accelerator Laboratory, Tsinghua University, Beijing 100084, China

摘要

摘要: 大规模激光相干合成是突破单口径激光特性极限、获得超高峰值/平均功率、超大脉冲能量、超高空/谱亮度等极端特性激光的有效技术路径之一，而大规模激光相干合成的关键是主动相位控制。主动相位控制技术可以对各路光束相位进行主动控制，补偿相位噪声引起的相干特性退化、合成效率下降，获得高品质的合成激光。自相干合成技术提出以来，研究人员开发了多种主动相位控制方法用于相干合成相位校正，其中适用于大规模激光相干合成的主动相位控制方法也得到了飞速发展。系统梳理了大规模激光相干合成的主动相位控制方法，深入分析了不同方法的原理、特点、适用场景和扩展能力，介绍了不同方法取得的相干合成研究最新进展及标志性成果，报道了19通道闭环上升时间仅6 μs的相干合成锁相控制突破性结果，最后总结和展望了主动相位控制方法的发展趋势。
- 相干合成 /
- 主动相位控制 /
- 多抖动 /
- 随机并行梯度下降 /
- 机器学习
Abstract: Large-scale coherent beam combining is one of the effective techniques to break through the limit of a single laser, and obtain laser with extreme characteristics such as ultra-high peak/average power, ultra-high pulse energy, ultra-high spatial/spectral brightness, and the key to large-scale coherent beam combining is active phase control. Active phase control technology can control the phase of each beam actively, compensate for coherence degradation and efficiency reduction caused by phase noise, and realize high-quality combined laser. Since the proposal of coherent beam combining technology, researchers have developed a variety of active phase control methods for phase correction, among which active phase control methods suitable for large-scale coherent laser beam combining have developed rapidly. In this paper, active phase control methods for large-scale coherent laser beam combining are systematically reviewed, and the principles, characteristics, application scenarios and expansibilities of different methods are analyzed; the latest progress and landmark achievements of coherent beam combining achieved by various active phase control methods are introduced, and the breakthrough result of 6 μs closed-loop locking time for 19-channel coherent beam combining is reported; the future development trend of large-scale active phase control methods is predicted.
- coherent beam combining /
- active phase control /
- multi-dithering /
- stochastic parallel gradient descent /
- machine learning

HTML全文

图 1 主动相位控制方法分类

Figure 1. Categories of active phase control methods

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图 2 倾斜干涉法测量相位的基本原理^[38]

Figure 2. Principle of phase measurement by inclined interference^[38]

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图 3 基于干涉法的61路飞秒脉冲光纤激光相干合成的（a）阵列结构、干涉条纹图像和（b）实验结果^[42]

Figure 3. (a) Array structure and interference fringe pattern and (b) experiment results of interference-based coherent beam combining of 61 femtosecond fiber lasers^[42]

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图 4 基于干涉法的1 027路相干合成的（a）系统结构和（b）实验结果^[44]

Figure 4. (a) System setup and (b) experiment results in interference-based coherent beam combining of 1 027 channels^[44]

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图 5 （a）107路SPGD相干合成实验系统及控制效果^[60]，（b）19路20 kW级SPGD相干合成的开环和闭环光斑图像^[17]

Figure 5. (a) Experiment system and control effect of 107-channel SPGD coherent beam combining^[60]，(b) beam pattern of 19-channel 20 kW class SPGD coherent beam combining^[17]

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图 6 基于SPGD算法的61路相干合成的开环和闭环归一化强度

Figure 6. Normalized intensity in open- and closed-loop of SPGD-based 61-channel coherent beam combining

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图 7 分级SPGD算法^[73]

Figure 7. Multi-stage SPGD^[73]

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图 8 多抖动法相干合成系统结构图

Figure 8. Diagram of coherent beam combining system based on multi-dithering method

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图 9 多抖动法32路相干合成控制前后的强度变化和闭环控制残差^[78]

Figure 9. Intensity comparison before and after control and closed-loop phase residual in 32-channel multi-dithering coherent beam combining^[78]

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图 10 基于高速多抖动法的19路相干合成的（a）实验光路图、（b）锁相上升时间；相位控制板的（c）带宽评估系统和（d）带宽测试结果

Figure 10. (a) Experiment setup and (b) phase-locking rising time of 19-channel coherent beam combining based on high-speed multi-dithering method. (c) Bandwidth evaluation system and (d) bandwidth test result of the phase control circuit

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图 11 基于级联多抖动法的2×4路相干合成^[86]

Figure 11. 2×4 coherent beam combining based on cascaded multi-dithering method^[86]

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图 12 PIM相位控制的系统设置^[87]

Figure 12. System setup of PIM phase control^[87]

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图 13 基于PIM的37路光纤放大器相干合成^[89]

Figure 13. PIM coherent beam combining of 37-channel fiber amplifiers^[89]

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图 14 PIM-PR控制方法^[88]

Figure 14. PIM-PR control method^[88]

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图 15 基于PIM的81路相干合成的DOE传输函数及模拟和实验光斑强度分布^[92]

Figure 15. DOE transmission function and intensity profile in simulation and experiment of 81-channel DOE coherent beam combining based on PIM^[92]

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图 16 CNN的建立和训练过程^[115]

Figure 16. Establishment and training process of CNN^[115]

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图 17 准强化学习100路相干合成的实验系统设置和收敛曲线^[100]

Figure 17. System setup and convergence curves of 100-channel CBC by quasi-reinforcement learning^[100]

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图 18 基于神经网络算法的81路相干合成^[120]

Figure 18. 81-channel coherent beam combining based on neural network algorithm^[120]

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图 19 CNN和SPGD算法（a）在不同初始条件下的7路合成收敛曲线和（b）收敛时间随路数的变化^[122]

Figure 19. (a) Convergence curve of 7-channel coherent beam combining under different initial conditions and (b) convergence time versus element number by CNN and SPGD^[122]

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图 20 DDRM算法相位控制的收敛曲线^[124]

Figure 20. Convergence curves of phase control by DDRM algorithm^[124]

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图 21 （a）传统损失函数和（b）周期损失函数训练的CNN在不同真实相位下的预测误差及其统计分布^[125]

Figure 21. Prediction errors and their statistic distribution for various true phases as CNN trained by (a) traditional and (b) periodical loss function^[125]

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表 1 大规模光纤激光相干合成的代表性成果

Table 1. Representative results of large-scale coherent beam combining of fiber lasers

year	number of channels	institution	method	single step time	rising time	residual
2011	64^[28]	Thales Research & Technology	interference	50 ms	−	λ/10
2011	32^[78]	University of New Mexico	multi-dithering	2.45 μs	−	λ/71
2017	37^[89]	Université de Limoges	PIM	−	1 ms	λ/25
2020	61^[42]	Thales Research & Technology	interference	1 ms	−	λ/55
2020	107^[60]	National University of Defense Technology	SPGD	1 μs	−	λ/22
2021	81^[92]	Lawrence Berkeley National Lab	PIM	33 ms	−	−
2021	81^[120]	Lawrence Berkeley National Lab	machine learning	～10 ms	～0.4 s	−
2022	61	China Academy of Engineering Physics	SPGD	−	～40 ms	λ/37
2022	100^[100]	Université de limoges	machine learning	0.4 s	～2.4 s	λ/30
2022	397^[43]	National University of Defense Technology	interference	5 ms	−	λ/31
2023	1027^[44]	National University of Defense Technology	interference	5 ms	−	λ/27
2023	19	China Academy of Engineering Physics	multi-dithering	2 μs	6 μs	λ/56

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表 2 主动相位控制方法的对比

Table 2. Comparison of active phase control methods

method	system requirement	execution rate	control bandwidth	optical complexity	algorithm complexity
interference	tiled aperture	slow	medium	high	medium
SPGD	none	medium	inversely proportional to channels	low	low
multi-dithering	none	fast	high	low	medium
PIM	DOE/tiled aperture	fast	high	medium	medium
machine learning	DOE/tiled aperture	slow	medium	low	high

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