Design and experimental verification of unequal-arm interferometric frequency stabilization scheme in taiji program
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摘要:
激光频率噪声是空间引力波探测系统的最大噪声源,计划采用PDH (Pound-Drever-Hall)锁腔预稳、锁臂和时间延迟干涉的方法学进行逐级压制。但随着皮米测量的发展,利用空间光不等臂干涉稳频,特别是可以有效的利用现有空间激光干涉仪,无需额外超稳载体,是目前较为热门的替代PDH锁腔预稳方案。本文在太极计划第一代干涉仪光学平台的基础上,验证了利用现有干涉光路进行不等臂干涉仪稳频的方案及其有效性。实验结果显示,自由运行激光器频率噪声整体降低约一个量级,1 Hz处提升至3 KHz/Hz1/2。通过噪声分析可以发现,在0.2 Hz−1 Hz频段,主要限制因素是干涉仪的背景噪声。在0.1 Hz−1 mHz频段内,主要为自由运行激光器的功率噪声。未来将进一步降低干涉仪噪声至1 pm/Hz1/2,探索利用已有干涉光路稳频替代PDH锁腔方案的可能性。
Abstract:Laser frequency noise is the dominant noise source in space-based gravitational wave detection systems. A multi-stage suppression approach is planned, employing PDH (Pound-Drever-Hall) cavity-locking pre-stabilization, arm-locking, and time-delay interferometry. However, with the advancement of picometer-level measurement, unequal-arm interferometric frequency stabilization using free-space laser links has emerged as a popular alternative to the PDH cavity-locking pre-stabilization scheme. This approach can effectively utilize existing space laser interferometers without requiring additional ultra-stable reference cavities. Based on the first-generation interferometric optical platform of the Taiji program, this paper verifies the feasibility and effectiveness of an unequal-arm interferometer frequency stabilization scheme using the existing interferometric optical path. Experimental results show that the free-running laser frequency noise is reduced by approximately one order of magnitude overall, reaching 3 kHz/Hz1/2 at 1 Hz. Noise analysis reveals that in the 0.2 Hz–1 Hz band, the main limiting factor is the background noise of the interferometer. In the 0.1 Hz–1 mHz band, the dominant noise source is the power noise of the free-running laser. Future work will focus on further reducing the interferometer noise to 1 pm/Hz1/2 and exploring the feasibility of replacing the PDH cavity-locking scheme with frequency stabilization using the existing interferometric optical path.
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图 1 干涉仪光学平台光路设计图 左:正面;右:背面
Figure 1. Optical path design of interference optical bench. Left: Front side; Right: Back side. M: mirror, BS: beam splitter (R/T: 50/50), BSa: beam splitter (10/90), BSb: beamsplitter (90/10), BSc: beam splitter (1/99), BSd: beam splitter (99/1), PBS: polarizing beam splitter, FIOS:fibre injector optical subassembly, P-A: periscope in side A, P-B: periscope in side B, HWP: half waveplate, QWP: quarter wave plate, Telescope-I/F: telescope interface, TM-I/F: test mass interface, PAAM:point ahead angle mechanism, BSMG: beam shrinking mirror group, QPD: quadrant photodiode.
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[1] HU W R, WU Y L. The Taiji Program in Space for gravitational wave physics and the nature of gravity[J]. National Science Review, 2017, 4(5): 685-686. doi: 10.1093/nsr/nwx116 [2] LUO Z R, GUO Z K, JIN G, et al. A brief analysis to Taiji: Science and technology[J]. Results in Physics, 2020, 16: 102918. doi: 10.1016/j.rinp.2019.102918 [3] LUO J, CHEN L SH, DUAN H Z, et al. TianQin: a space-borne gravitational wave detector[J]. Classical and Quantum Gravity, 2016, 33(3): 035010. doi: 10.1088/0264-9381/33/3/035010 [4] LUO J, BAI SH J, BAI Y ZH, et al. Progress of the TianQin project[J]. Classical and Quantum Gravity, 2025, 42(17): 173001. doi: 10.1088/1361-6382/adda8a [5] The LISA Pathfinder Team, The eLISA Consortium. LISA and its pathfinder[J]. Nature Physics, 2015, 11(8): 613-615. doi: 10.1038/nphys3420 [6] 王娟, 齐克奇, 王少鑫, 等. 面向空间引力波探测的激光干涉技术研究进展及展望[J]. 中国科学: 物理学 力学 天文学, 2024, 54(7): 270405. doi: 10.1360/SSPMA-2024-0111WANG J, QI K Q, WANG SH X, et al. Advance and prospect in the study of laser interferometry technology for space gravitational wave detection[J]. Scientia Sinica Physica, Mechanica & Astronomica, 2024, 54(7): 270405. (in Chinese). doi: 10.1360/SSPMA-2024-0111 [7] 刘河山, 王娟, 高瑞弘, 等. 太极二号干涉仪系统噪声与指标分解[J]. 空间科学学报, 2025, 45(4): 1047-1057. doi: 10.11728/cjss2025.04.2025-yg02LIU H SH, WANG J, GAO R H, et al. Noise and index decomposition of Taiji-2 interferometer system[J]. Chinese Journal of Space Science, 2025, 45(4): 1047-1057. (in Chinese). doi: 10.11728/cjss2025.04.2025-yg02 [8] FAN X, FAYER S E, MYERS T G, et al. Switchable damping for a one-particle oscillator[J]. Review of Scientific Instruments, 2021, 92(2): 023201. doi: 10.1063/5.0038005 [9] LI Y Q, LUO Y, LAI J T, et al. An advanced digital controller with automatic design for laser frequency stabilization in space[J]. Review of Scientific Instruments, 2025, 96(8): 084502. doi: 10.1063/5.0272346 [10] 骆颖欣. 星载激光稳频原理演示系统的研制[D]. 武汉: 华中科技大学, 2016.LUO Y X. Establishment of a preliminary prototype of the spaceborne laser-frequency-stabilization system[D]. Wuhan: Huazhong University of Science and Technology, 2016. (in Chinese). [11] 彭建康. 星载全固态Nd: YAG单块非平面环形腔激光及稳频用参考腔的研制[D]. 武汉: 中国科学院大学(中国科学院精密测量科学与技术创新研究院), 2025.PENG J K. Development of a spaceborne all-solid-state Nd: YAG nonplanar-ring-oscillator laser and the reference cavity for frequency stabilization[D]. Wuhan: University of Chinese Academy of Sciences, 2025. (in Chinese). [12] 程飞虎. 用于长度标准的532 nm碘分子频率标准的研究[D]. 武汉: 华中科技大学, 2021.CHENG F H. Study of a 532-nm molecular-iodine frequency standard as a length standard[D]. Wuhan: Huazhong University of Science & Technology, 2021. (in Chinese). [13] 支允琳. 碘分子激光稳频及其中剩余幅度调制的研究[D]. 武汉: 中国科学院大学(中国科学院精密测量科学与技术创新研究院), 2022.ZHI Y L. Laser frequency stabilization with iodine molecules and investiagation on residual amplitude modulation[D]. Wuhan: University of Chinese Academy of Sciences, 2022. (in Chinese). [14] 董靖. 超低噪声光纤干涉仪稳频激光器实验研究[D]. 北京: 中国科学院大学, 2016.DONG J. Experimental research on ultra-low noise fiber interferometer stabilized laser[D]. Beijing: University of Chinese Academy of Sciences, 2016. (in Chinese) (查阅网上资料, 未找到本条文献英文翻译信息, 请确认). [15] SHI B, EDREIRA I B, DING M, et al. Laser stabilized to a fiber interferometer with close-to-zero temperature sensitivity[J]. Laser & Photonics Reviews, 2026, 20(8): e02000. doi: 10.1002/lpor.202502000 [16] GERBERDING O, ISLEIF K S, MEHMET M, et al. Laser-frequency stabilization via a quasimonolithic mach-zehnder interferometer with arms of unequal length and balanced dc readout[J]. Physical Review Applied, 2017, 7(2): 024027. doi: 10.1103/PhysRevApplied.7.024027 [17] HUARCAYA V, ÁLVAREZ M D, PENKERT D, et al. 2×10-13 fractional laser-frequency stability with a 7-cm unequal-arm mach-zehnder interferometer[J]. Physical Review Applied, 2023, 20(2): 024078. doi: 10.1103/PhysRevApplied.20.024078 [18] DI FRONZO C, HOLLAND N A, MITCHELL A L, et al. Laser frequency stabilization with the use of homodyne quadrature interferometers[J]. Classical and Quantum Gravity, 2024, 41(6): 065010. doi: 10.1088/1361-6382/ad13c4 [19] HUARCAYA V, DOVALE ÁLVAREZ M, YAMAMOTO K, et al. Single-element dual-interferometer for precision inertial sensing: sub-picometer structural stability and performance as a reference for laser frequency stabilization[J]. Sensors, 2023, 23(24): 9758. doi: 10.3390/s23249758 [20] ARMANO M, AUDLEY H, BAIRD J, et al. Sensor noise in LISA Pathfinder: in-flight performance of the optical test mass readout[J]. Physical Review Letters, 2021, 126(13): 131103. doi: 10.1103/PhysRevLett.126.131103 [21] ARMANO M, AUDLEY H, BAIRD J, et al. Sensor noise in LISA Pathfinder: an extensive in-flight review of the angular and longitudinal interferometric measurement system[J]. Physical Review D, 2022, 106(8): 082001. doi: 10.1103/PhysRevD.106.082001 [22] WANG J, QI K Q, LIU H SH, et al. An integrated fiber phase modulation device for optical path noise suppression[J]. Classical and Quantum Gravity, 2026, 43(1): 015001. doi: 10.1088/1361-6382/ae28ac [23] CAO B, JIA F L, YANG M L, et al. Suppression of frequency-mixing effect for pm-level heterodyne interferometers based on “zero coupling” optical path length control[J]. Optics Letters, 2024, 49(12): 3300-3303. doi: 10.1364/OL.523455 [24] 范习谦, 刘河山, 罗子人, 等. 基于MHz深度频率调制激光干涉的相位测量技术[J]. 中国光学(中英文), 2025, 18(3): 622-630.FAN X Q, LIU H SH, LUO Z R, et al. Phase measurement technique based on MHz-lever depth frequency modulated laser interferometry[J]. Chinese Optics, 2025, 18(3): 622-630. (in Chinese) [25] LIU H SH, WANG J, TAO W, et al. Recent development of the laser interferometer for Taiji Space gravitational wave detection[J]. Research, 2026, 9: 1252. doi: 10.34133/research.1252 [26] FENG Y J, JIANG Y Z, CHEN L Y, et al. Influence mechanism of truncation on low-frequency phase measurement[J]. Measurement, 2026, 259: 119594. doi: 10.1016/j.measurement.2025.119594 [27] YANG R, LUO Z R, LIU H SH. Limitations and improvements in low-frequency performance of phasemeter for space gravitational wave detection[J]. Measurement, 2026, 260: 119825. doi: 10.1016/j.measurement.2025.119825 [28] YANG R, LIU H SH, LUO Z R. Optimization design of decimation filter for the phasemeter in the space gravitational wave detection[J]. IEEE Transactions on Instrumentation and Measurement, 2024, 73: 7006508. doi: 10.1109/tim.2024.3453345 [29] 张强涛, 刘河山, 罗子人. 面向空间激光干涉的多通道相位测量系统[J]. 中国光学(中英文), 2023, 16(5): 1089-1099. doi: 10.37188/CO.2022-0258ZHANG Q T, LIU H SH, LUO Z R. Multi-channel phase measurement system for the space laser interferometry[J]. Chinese Optics, 2023, 16(5): 1089-1099. (in Chinese). doi: 10.37188/CO.2022-0258 [30] 王晨, 高雪荣, 齐克奇, 等. 太极计划的弱光锁相地面实验验证及噪声分析[J]. 中国激光, 2025, 52(11): 1101004. doi: 10.3788/CJL241485WANG CH, GAO X R, QI K Q, et al. Weak-light phase-locked ground-based experimental validation and noise analysis of the Taiji Program[J]. Chinese Journal of Lasers, 2025, 52(11): 1101004. (in Chinese). doi: 10.3788/CJL241485 [31] LIANG Y R, FENG Y J, XIAO G Y, et al. Experimental scheme and noise analysis of weak-light phase locked loop for large-scale intersatellite laser interferometer[J]. Review of Scientific Instruments, 2021, 92(12): 124501. doi: 10.1063/5.0058659 [32] 陈沛权, 邓汝杰, 张艺斌, 等. 太极计划星间激光通信测距的伪随机码选取[J]. 中国光学(中英文), 2025, 18(3): 547-556. doi: 10.37188/CO.2024-0033CHEN P Q, DENG R J, ZHANG Y B, et al. Pseudo-random code selection for inter-satellite laser ranging and data communication in the Taiji program[J]. Chinese Optics, 2025, 18(3): 547-556. (in Chinese). doi: 10.37188/CO.2024-0033 [33] LIANG H Q, YI ZH X, LING H L, et al. Modeling and simulation of inter-satellite laser communication for space-based gravitational wave detection[J]. Sensors, 2025, 25(4): 1068. doi: 10.3390/s25041068 [34] 张子恒, 范习谦, 靳刚, 等. 太极计划激光链路辅助功能方案设计及验证[J]. 中国激光, 2025, 52(11): 1106001. doi: 10.3788/CJL241483ZHANG Z H, FAN X Q, JIN G, et al. Design and verification of a laser link auxiliary function scheme for the Taiji Program[J]. Chinese Journal of Lasers, 2025, 52(11): 1106001. (in Chinese). doi: 10.3788/CJL241483 -
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