Investigation of an Ultra High Signal-to-noise Ratio Physics Package for the Rubidium Atomic Clock

doi:10.11938/cjmr20233056

Abstract

Abstract:

Driven by the demand for satellite navigation and deep space exploration, the performance of lamp-pumped rubidium atomic clock has been greatly improved, and its short-term frequency stability has reached the level of a small coefficient of 10^-13τ ^-1/2. To further improve the frequency stability of rubidium clock and explore its performance limit, this article is based on the redesign and experimental verification of the structure of the physical package (PP, Φ40 microwave cavity) in the early stage, with a comprehensively optimized design of the optical system of PP, the performance of the spectral lamp and pumping light has been enhanced. Finally, the SNR of PP has been significantly increased. The test and evaluation results showed that the contribution of the shot noise of the newly designed PP to the frequency stability of rubidium clock is 4.2×10^-14τ ^-1/2. The results of this research lay the foundation for the short-term stability of rubidium clocks to achieve 5×10^-14τ ^-1/2, and the long-term stability to break through 1×10^-15.

Key words: rubidium atomic clock, physics package, signal-to-noise ratio, spectral lamp, frequency stability

CLC Number:

O482.53

CUI Jiaqi, LIU Kangqi, LI Junyao, WANG Fang, MING Gang, ZHAO Feng, MEI Ganghua, ZHONG Da. Investigation of an Ultra High Signal-to-noise Ratio Physics Package for the Rubidium Atomic Clock[J]. Chinese Journal of Magnetic Resonance, 2023, 40(4): 462-470.

Figures/Tables 7

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

References 15

[1]	VANNICOLA F, BEARD R, WHITE J, et al. GPS block IIF atomic frequency standard analysis[C]// Proceedings of the 42nd Annual Precise Time and Time Interval Systems and Applications Meeting, Reston, Virginia, 2010: 181-196.
[2]	JADUSZLIWER B, CAMPARO J. Past, present and future of atomic clocks for GNSS[J] GPS Solutions, 2021, 25(1): 1-13. doi: 10.1007/s10291-020-01037-3
[3]	MALEKI L, PRESTAGE J. Applications of clocks and frequency standards: from the routine to tests of fundamental models[J] Metrologia, 2005, 42(3): S145. doi: 10.1088/0026-1394/42/3/S15
[4]	RILEY J W. Rubidium atomic frequency standards for GPS block IIR[C]// Proceedings of 22nd Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting, Vienna, Virginia, 1990: 221-230.
[5]	MEI G H, ZHAO F, Qi F, et al. Characteristics of the space-borne rubidium atomic clocks for the BeiDou III navigation satellite system[J]. Sci Sin-Phys Mech As, 2021, 51(1): 118-124.
[6]	CUI J Q, MING G, WANG F, et al. Design and studies of an ultra high-performance physics package for vapor-cell rubidium atomic clock[C]// 2022 Proceedings of China satellite navigation conference (CSNC), Springer, 2022: 403-414.
[7]	LI J, ZHANG J H, BU Y N, et al. Space passive hydrogen maser a passive hydrogen maser for space applications[C]// Proceedings 2016 IEEE International Frequency Control Symposium (IFCS), IEEE, 2016: 1-5.
[8]	BANDI T, AFFOLDERBACH C, STEFANUCCI C. et al, Compact high-performance continuous-wave double-resonance rubidium standard with 1.4×10^-13τ^-1/2 stability[J]. IEEE T Ultrason Ferr, 2014, 61 (11): 1769-1778. doi: 10.1109/TUFFC.2013.005955
[9]	FRANÇOIS B, CALOSSO C E, ABDEL H, et al. Simple-design ultra-low phase noise microwave frequency synthesizers for high-performing Cs and Rb vapor-cell atomic clocks[J] Rev Sci Instrum, 2015, 86(9): 094707. doi: 10.1063/1.4929384
[10]	VANIER J, AUDOIN C. The Quantum Physics of Atomic Frequency Standards[M]. 1st ed.ed. Bristol and Philadelphia: Adam Hilger, 1989.
[11]	MILETI G, DENG J, WALLS F, et al. Recent progress in laser-pumped rubidium gas-cell frequency standards[C]// 1996 IEEE International Frequency Control Symposium (IFCS), IEEE, 1996: 1066-1072.
[12]	CAMPARO J, HUDSON A. Mesoscopic physics in vapor-cell atomic clocks[C]// 2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS), IEEE, 2017: 47-54.
[13]	CAMPARO J, MACKAY R. Spectral mode changes in an alkali RF discharge[J] J Appl Phys, 2007, 101(5): 053303. doi: 10.1063/1.2435914
[14]	XU F, HAO Q, WANG P F, et al. A high signal to noise ratio physics package with a slotted-tube cavity for rubidium atomic clock[J]. Acta Metrologica Sinica, 2016, 37(4): 437-440.
	许风, 郝强, 王鹏飞, 等. 基于开槽管腔的高信噪比铷原子钟物理系统[J]. 计量学报, 2016, 37(4): 437-440.
[15]	NIE S, WANG P F, ZHAO F, et al. A physics package with shot-noise limited frequency stability better than 1×10^-13τ^-1/2 for rubidium atomic frequency standards[J]. Chinese J Magn Reson, 2022, 39(1): 108-114.
	聂帅, 王鹏飞, 赵峰, 等. 散弹噪声极限稳定度优于1×10^-13τ^-1/2的铷频标物理系统[J]. 波谱学杂志, 2022, 39(1): 108-114.