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

Zhou Hongbing; Zhang Haoyu; Li Min; Feng Xi; Xie Lianghua; Liu Yu; Chu Qiuhui; Yan Yuefang; Tao Rumao; Lin Honghuan; Wang Jianjun; Yan Lixin; Jing Feng

doi:10.11884/HPLPB202436.230426

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Zhou Hongbing, Zhang Haoyu, Li Min, et al. Progress in active phase control for large-scale coherent laser beam combining[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202436.230426

Citation:

Zhou Hongbing, Zhang Haoyu, Li Min, et al. Progress in active phase control for large-scale coherent laser beam combining[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202436.230426

Zhou Hongbing, Zhang Haoyu, Li Min, et al. Progress in active phase control for large-scale coherent laser beam combining[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202436.230426

Citation:

Zhou Hongbing, Zhang Haoyu, Li Min, et al. Progress in active phase control for large-scale coherent laser beam combining[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202436.230426

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

doi: 10.11884/HPLPB202436.230426

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

Received Date: 2023-12-01
Accepted Date: 2024-03-11
Rev Recd Date: 2024-03-11

Available Online: 2024-03-25

Abstract

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

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References(125)

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