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孙仕豪; 郑也; 于淼; 李思源; 曹镱; 王军龙; 王学锋

doi:10.37188/CO.2023-0074

365彩票官网彩票

doi: 10.37188/CO.2023-0074

北京航天控制仪器研究所, 北京 100094

基金项目:国家自然科学基金企业创新发展联合基金(No. U20B2058)

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- 网络出版日期: 2023-09-22

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Beijing Institute of Aerospace Control Devices, Beijing 100094, China

Funds:Supported by National Natural Science Foundation of China (No. U20B2058)

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Corresponding author: [email protected]; [email protected]; [email protected]

摘要

摘要:
基于多纵模振荡种子源的窄线宽光纤激光器具有光路简单、结构紧凑、可靠性高、成本低等特点，在实际工程应用以及在空间受限的载荷平台上有着显著优势，是高功率光谱合成的理想子束模块。受自脉冲效应的影响，多纵模振荡种子源的时域特性较差，导致了放大过程中产生较强的光谱展宽与受激拉曼散射效应，这限制了输出功率的进一步提升并降低了其光谱纯度。本文首先介绍了四种常见的窄线宽种子源，并重点分析了多纵模振荡种子源中自脉冲效应的产生机理及抑制方法，对优化多纵模振荡种子源和放大器的关键技术进行了详细介绍，归纳总结了近几年的技术突破与研究成果，对未来的发展方向进行了展望分析，为基于多纵模振荡种子源的窄线宽激光器的功率提升和光谱优化提供一定思路。
- 窄线宽 /
- 光纤激光器 /
- 多纵模振荡种子源 /
- 自脉冲 /
- 复合腔
Abstract:
Narrow linewidth fiber lasers, which are based on a oscillator seed source with multiple longitudinal-mode, offer substantial advantages for engineering applications and space-limited platform payloads. Additionally, they are considered ideal sub-modules for high-power spectral combinations. The time domain of this type of seed is unstable due to the self-pulse effect, causing significant spectral broadening and stimulated Raman scattering effects during the amplification process, which limits their further application. This paper introduces four commonly used narrow linewidth seeds. The mechanism and suppression methods of the self-pulse effect in multi-longitudinal mode oscillator seeds were analyzed. Critical technologies essential for the optimization and relevant progress of the multi-longitudinal-mode oscillator seed source and amplifier stages are discussed in detail. A future development outlook is also presented. This paper serves as a useful reference for the design of narrow linewidth fiber lasers based on the multi-longitudinal-mode oscillator seed source.
- Narrow linewidth /
- fiber laser /
- multi-longitudinal-mode oscillator seed /
- self-pulse effect /
- complex oscillator cavity

HTML全文

图 1 不同窄线宽种子源示意图，（a）单频激光相位调制种子源，（b）超荧光光源窄带滤波种子源，（c）随机光纤激光器种子源，（d）多纵模振荡种子源

Figure 1. Schematic diagram of different narrow-linewidth seed source, (a) single frequency laser modulation seed source, (b) narrow band filtered seed source of superfluorescent light, (c) random fiber laser seed source, (d) narrow-linewidth multi-longitudinal-mode oscillator seed source

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图 2 不同功率和时间尺度上的自脉冲时域信号，（a）在微秒尺度上的激光阈值自脉冲，（b）在十纳秒尺度上的激光阈值自脉冲，（c）在微秒尺度上的较高功率激光自脉冲，（d）在十纳秒尺度上的较高功率激光自脉冲^{[
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Figure 2. Time-domain signals of self-pulse at different time scales and power, (a) laser threshold self-pulse on the microsecond scale, (b) laser threshold self-pulse on the ten nanosecond scale, (c) laser threshold self-pulse with higher power on the microsecond scale, (d) laser threshold self-pulse with higher power on the ten nanosecond scale ^{[
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图 3 不同带宽输出耦合光栅构成的振荡腔时域测试结果^{[
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Figure 3. Time-domain test results of oscillator with different OC-FBGs of different bandwidths^{[
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图 4 输出功率为18.25 W时的时序特性，（a）不同腔长在微秒尺度下的时序特性，（b）不同腔长在纳秒尺度下的时序特性^{[
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Figure 4. Time-domain signals when the output power is 18.25 W, (a) different oscillator lengths on a microsecond scale, (b) different oscillator lengths on a nanosecond scale^{[
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图 5 空间耦合F-P腔抑制自脉冲实验，（a）不含F-P腔和（b）含F-P腔的示意图

Figure 5. Schematic diagram of self-pulse suppression experiment, (a) with and (b) without spatially F-P cavity

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图 6 全光纤化复合腔抑制自脉冲实验，复合振荡腔示意图

Figure 6. Schematic diagram of complex oscillator cavity in the all-fiber-optic complex cavity suppression self-pulse experiment

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图 7 基于振荡腔种子级的高功率激光光谱，（a）对单振荡腔种子光进行放大后的激光光谱，（b）对复合振荡腔种子光进行放大后的激光光谱^{[
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Figure 7. High power laser spectra based on different oscillator cavities, (a) laser spectra after amplification of single oscillator cavity, (b) laser spectra after amplification of complex oscillator cavity^{[
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图 8 引入CTFBG前后，1 kW窄线宽激光的SRS抑制情况

Figure 8. SRS suppression of 1 kW narrow line-width fiber laser with and without CTFBG

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图 9 光路示意图（a）常规腔型种子源,（b）复合腔种子源，（c）加长复合腔种子源，（d）放大级光路图

Figure 9. Schematic diagram of optical path of (a) ordinary oscillator cavity seed, (b) complex oscillator cavity seed, (c) long complex oscillator cavity seed, (d) amplifier stage

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图 10 基于复合腔振荡种子源的窄线宽单级MOPA结构激光系统示意图

Figure 10. Schematic diagram of a narrow-linewidth single stage MOPA configuration laser system based on a complex cavity oscillator seed source

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图 11 1045 nm窄线宽光纤激光器光路示意图

Figure 11. Schematic diagram of narrow-linewidth fiber laser at 1045 nm

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图 12 3.3 kW窄线宽光纤激光器光路示意图

Figure 12. Schematic diagram of the optical path of a 3.3 kW narrow-linewidth fiber laser

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图 13 “种子-放大级共享泵浦”结构示意图

Figure 13. Schematic diagram of the structure of the “seed-amplifier sharing pump”

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图 14 不同泵浦方式的线宽变化规律

Figure 14. The variation of linewidth with different pumping methods

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