基于空间结构内部锁相的光纤激光相干合成技术

龙金虎; 粟荣涛; 常洪祥; 侯天悦; 常琦; 蒋敏; 张嘉怡; 马阎星; 马鹏飞; 周朴

doi:10.11884/HPLPB202335.220258

基于空间结构内部锁相的光纤激光相干合成技术

doi: 10.11884/HPLPB202335.220258

龙金虎^1,,
粟荣涛^{1, 2, 3, ,},
常洪祥¹,
侯天悦¹,
常琦¹,
蒋敏¹,
张嘉怡¹,
马阎星^{1, 2, 3},
马鹏飞^{1, 2, 3},
周朴^1, ,

1.
国防科技大学前沿交叉学科学院，长沙 410073
2.
国防科技大学南湖之光实验室，长沙 410073
3.
国防科技大学高能激光技术湖南省重点实验室，长沙 410073

基金项目: 国家自然科学基金项目(62275272, 62075242); 湖南省自然科学基金创新研究群体项目(2019JJ10005); 长沙市优秀青年创新人才培养计划项目(kq2206003); 湖南省研究生科研创新项目(QL20220013)

详细信息

作者简介:
龙金虎，ljh65923@163.com

通讯作者:
粟荣涛，surongtao@126.com

周　朴，zhoupu203@163.com

中图分类号: TN248.1
计量
- 文章访问数: 1078
- HTML全文浏览量: 434
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- 被引次数: 0
出版历程
- 收稿日期: 2022-08-23
- 修回日期: 2022-09-28
- 录用日期: 2022-11-17
- 网络出版日期: 2022-11-18
- 刊出日期: 2023-03-30

Coherent combining of fiber laser based on internal phase locking in spatial structure

Long Jinhu^1
,,
Su Rongtao^{1, 2, 3
, ,},
Chang Hongxiang¹,
Hou Tianyue¹,
Chang Qi¹,
Jiang Min¹,
Zhang Jiayi¹,
Ma Yanxing^{1, 2, 3},
Ma Pengfei^{1, 2, 3},
Zhou Pu^{1
, ,}

1.
College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
2.
Nanhu Laser Laboratory, National University of Defense Technology, Changsha 410073, China
3.
Hunan Provincial Key Laboratory of High Energy Laser Technology, National University of Defense Technology, Changsha 410073, China

摘要

摘要: 介绍了本课题组近年来在基于空间结构内部锁相的光纤激光相干合成方面的研究工作，给出了空间结构内部锁相相干合成的基本原理,搭建了七路低功率光纤激光阵列实验系统，结果表明在内部相位噪声校正基础之上，可以稳定补偿外部相位差进而实现激光阵列同相位输出，验证了内部锁相方法的可行性。进一步介绍了空间结构内部锁相技术在目标在回路相干合成、阵列光束光场调控等方面的拓展应用，通过实验论证了空间结构内部锁相技术能够有效提升目标在回路相干合成系统的相位控制带宽，并在远场有效生成轨道角动量光束阵列，其拓扑荷数可从−1到+1切换。
- 光纤激光 /
- 相干合成 /
- 相位控制 /
- 内部锁相 /
- 光场调控
Abstract: This paper introduces our recent research on the coherently combined fiber laser based on spatial structure internal phase locking including the principle of spatial structure internal phase locking, and the experiment of 7-channel fiber laser array carried out to experimentally verify the feasibility of this technique. The detailed results indicate that when the phase noises in the laser channels are locked, the external phase differences an be compensated together, and the laser array can be locked with a same phase wavefront. In addition, the researches on the CBC of target in the loop (TIL) technique and constructing the light fields are introduced as well. In the experiment, the control bandwidth of the CBC system of TIL could be improved effectively, and the orbital angular momentum beams could be generated in the far field, the topological charge could be changed from −1 to +1.
- fiber laser /
- coherent beam combining /
- phase control /
- internal phase control /
- constructing light field

HTML全文

图 1 光纤激光相干合成系统示意图^[52]

Figure 1. System configuration of fiber laser coherent combining based on internal phase locking^[52]

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图 2 光纤激光内部锁相相干合成实验系统^[52]

Figure 2. Experimental setup of coherent fiber laser array based on internal phase control^[52]

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图 3 CCD1采集到的采样阵列的强度分布当相位控制器1^[52]

Figure 3. Irradiance distribution of the sampled array detected by CCD1 before and after turning on Controller 1^[52]

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图 4 实验系统及开环实验结果和闭环实验结果^[52]

Figure 4. Experimental system, result of open-loop and result of closed-loop^[52]

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图 5 发射阵列的强度分布

Figure 5. Irradiance distribution of the emitted array

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图 6 基于空间结构内部锁相的目标在回路相干合成示意图

Figure 6. Schematic drawing of TIL-CBC based on internal phase control

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图 7 近场相干合成的实验结果^[61]

Figure 7. Experimental results of coherent beam combining (CBC) in the near field^[61]

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图 8 目标处合成光束的强度分布^[61]

Figure 8. Intensity distributions of combined beams on the target^[61]

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图 9 取样阵列实验结果^[85]

Figure 9. Experimental results of sampled laser array^[85]

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图 10 合成OAM光束的理论和实验结果^[85]

Figure 10. Theoretical and experimental results of the combined OAM beams^[85]

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图 11 干涉实验系统及结果^[84]

Figure 11. Results of interferometric experiment^[84]

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