Article
Physics, Multidisciplinary
R. Lange, N. Huntemann, J. M. Rahm, C. Sanner, H. Shao, B. Lipphardt, Chr Tamm, S. Weyers, E. Peik
Summary: A study compared two optical clocks based on Yb-171+ and measured the frequency ratio of their electric quadrupole and electric octupole transitions, finding improved accuracy. The study also analyzed potential violations of physical laws and improved limits on the temporal variations of fundamental constants and the proton-to-electron mass ratio.
PHYSICAL REVIEW LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Lee Cosart, Helmut Imlau, George Zampetti
Summary: This article introduces a new work item, the cnPRTC, being studied by the International Telecommunications Union (ITU) to provide highly accurate and resilient time for telecommunications networks. Unlike traditional approaches, the cnPRTC combines multiple independent sources of time and frequency to improve accuracy and resilience, creating a timescale concept.
IEEE COMMUNICATIONS MAGAZINE
(2023)
Article
Engineering, Multidisciplinary
Wei Xie, Guanwen Huang, Le Wang, Pingli Li, Bobin Cui, Haohao Wang, Yu Cao
Summary: The study reveals the long-term performance of GLONASS satellite clocks for the first time, showing average phase and frequency jump numbers, fitting precision, and clock stability evaluation. The results indicate that the short-term clock offset prediction accuracy and frequency stability of GLONASS clocks are inferior to other satellite systems.
Proceedings Paper
Engineering, Electrical & Electronic
Yani Zuo, Shaoyang Dai, Shiying Cao, Kun Liu, Weiliang Chen, Lei Han, Fangsong Zheng, Tianchu Li, Fang Fang
Summary: This paper proposes a design of the optical system for an optical atomic clock based on a single 171-ytterbium ion at NIM, covering ionization, cooling, repump, interrogation, and detection requirements.
OPTICAL SENSORS 2021
(2021)
Article
Instruments & Instrumentation
Sifei Chen, Chen Liu, Lifeng Fan, Chaojie Li, Yuanhao Li, Chang Liu, Yanhui Wang
Summary: We propose a new scheme for magnetic state selection in optically detected compact cesium beam clocks. By pointing the atomic collimator to the convex pole of the magnet, we select atoms in the desired ground state and avoid the undesired states, reducing fluorescence background. The scheme improves the signal contrast and short-term frequency stability significantly.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Physics, Applied
J. W. Pollock, V. I. Yudin, A. V. Taichenachev, M. Yu. Basalaev, D. V. Kovalenko, A. Hansen, J. Kitching, W. R. McGehee
Summary: This letter investigates the impact of coherent population trapping (CPT) on microwave atomic clocks in atomic vapors. The authors demonstrate that nonlinear light shifts in CPT clocks can arise from spatially inhomogeneous CPT driving fields. The results provide insights for improving light shift mitigation techniques.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Matteo Barbiero, Davide Calonico, Filippo Levi, Marco G. Tarallo
Summary: We report on the realization of a new compact strontium optical clock using a 2-D magneto-optical-trap (2D-MOT) as cold atomic source and a multi-wavelength cavity as the frequency stabilization system. The clock operation is performed without atomic signal normalization, enabling low-noise operation. Stability tests and preliminary accuracy budget demonstrate the feasibility of the system.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Acoustics
Daphna G. Enzer, David W. Murphy, Eric A. Burt
Summary: This article discusses the impact of local oscillators on the output of atomic clocks and how corrections through a control algorithm can optimize clock performance. By analyzing the Allan deviation of the output frequency, disturbances observed on the clock output can be diagnosed, with the corrections-ADEV used as a diagnostic tool.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2021)
Review
Acoustics
Bonnie L. Schmittberger Marlow, David R. Scherer
Summary: This paper discusses the importance of atomic frequency standards in modern life and the trends in commercial and emerging technologies. It provides a summary of the performance and operation principles of current atomic frequency standards, as well as the development direction of future emerging technologies.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2021)
Article
Optics
V. I. Yudin, M. Yu. Basalaev, A. Taichenachev, O. N. Prudnikov, D. A. Radnatarov, S. M. Kobtsev, S. M. Ignatovich, M. N. Skvortsov
Summary: We theoretically study the frequency shift caused by the line-shape asymmetry of coherent population trapping (CPT) resonance in a bichromatic laser field. The shift depends on the intensity of the resonant fields and leads to a degradation in long-term stability. We propose a frequency stabilization method based on the harmonic modulation of two-photon detuning to significantly suppress this shift.
Article
Physics, Multidisciplinary
A. Duspayev, G. Raithel
Summary: We report measurements of the hyperfine-structure constants of the Rb-85 4D(3/2) state using two-photon optical spectroscopy. The spectra were obtained by measuring the transmission of a low-power laser beam through a cold-atom sample. The dominant systematic error was addressed by extrapolating line positions measured for different laser powers. The results provide valuable information for precision metrology, atom-based quantum technologies, and molecular physics.
NEW JOURNAL OF PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Gaspare Antona, Michele Gozzelino, Salvatore Micalizio, Claudio E. Calosso, Giovanni A. Costanzo, Filippo Levi
Summary: This article describes a technique based on a frequency-to-voltage converter that can convert laser frequency fluctuations into voltage fluctuations, thus characterizing the laser frequency noise power spectral density in a wide range of Fourier frequencies.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Engineering, Electrical & Electronic
Hui Zhang, Jun Ruan, Dandan Liu, Fan Yang, Sichen Fan, Yang Bai, Yong Guan, Xinliang Wang, Junru Shi, Shougang Zhang
Summary: This article presents the design and preliminary operation results of an Rb-87 atomic fountain continuous clock developed at the National Time Service Center. The clock exhibits excellent stability due to improved design and suppression of unwanted effects. The clock's frequency stability and drift relative to UTC(NTSC) are discussed.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Review
Physics, Multidisciplinary
Sifei Chen, Chang Liu, Lifeng Fan, Chen Liu, Yuanhao Li, Shaohang Xu, Chaojie Li, Yanhui Wang
Summary: This paper presents an overview of the optically detected magnetic-state-selected cesium beam clock (OMCC) and discusses its technical issues, noise sources, frequency shifts, and improvements. The frequency stability of five OMCC is also compared to that of the high-performance version of Microsemi 5071A.
FRONTIERS IN PHYSICS
(2022)
Article
Acoustics
Clement Carle, Michael Petersen, Nicolas Passilly, Moustafa Abdel Hafiz, Emeric de Clercq, Rodolphe Boudot
Summary: Ramsey spectroscopy was investigated for the development of a microcell atomic clock based on CPT, improving short-term frequency stability. The study showed that Ramsey-CPT interrogation could enhance clock stability for averaging times over 100 seconds.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2021)
Article
Optics
R. Kaewuam, A. Roy, T. R. Tan, K. J. Arnold, M. D. Barrett
JOURNAL OF MODERN OPTICS
(2018)
Article
Physics, Multidisciplinary
T. R. Tan, R. Kaewuam, K. J. Arnold, S. R. Chanu, Zhiqiang Zhang, M. S. Safronova, M. D. Barrett
PHYSICAL REVIEW LETTERS
(2019)
Article
Physics, Multidisciplinary
R. Kaewuam, T. R. Tan, K. J. Arnold, S. R. Chanu, Zhiqiang Zhang, M. D. Barrett
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Multidisciplinary
K. J. Arnold, R. Kaewuam, S. R. Chanu, T. R. Tan, Thiqiang Zhang, M. D. Barrett
PHYSICAL REVIEW LETTERS
(2020)
Article
Multidisciplinary Sciences
Zhiqiang Zhang, Kyle J. Arnold, Rattakorn Kaewuam, Murray D. Barrett
Summary: The extreme precision of optical atomic clocks has led to the anticipated redefinition of the second. The accuracy of 1 part in 10^18 and beyond enables new applications and practical implementation of clocks. High-accuracy comparisons between two 176Lu+ references using correlation spectroscopy demonstrate agreement at the low 10^-18 level, with the lowest reported uncertainty in the frequency difference.
Article
Optics
Zhang Zhiqiang, K. J. Arnold, R. Kaewuam, M. S. Safronova, M. D. Barrett
Article
Optics
R. Kaewuam, T. R. Tan, Zhiqiang Zhang, K. J. Arnold, M. S. Safronova, M. D. Barrett
Article
Optics
Zhiqiang Zhang, K. J. Arnold, S. R. Chanu, R. Kaewuam, M. S. Safronova, M. D. Barrett
Article
Optics
M. D. Barrett, K. J. Arnold, M. S. Safronova
Article
Optics
K. J. Arnold, S. R. Chanu, R. Kaewuam, T. R. Tan, L. Yeo, Zhiqiang Zhang, M. S. Safronova, M. D. Barrett
Article
Optics
K. J. Arnold, R. Kaewuan, T. R. Tan, M. D. Barrett
Article
Optics
R. Kaewuam, T. R. Tan, K. J. Arnold, M. D. Barrett
Article
Optics
K. J. Arnold, R. Kaewuam, T. R. Tan, S. G. Porsev, M. S. Safronova, M. D. Barrett
Article
Optics
Zhiqiang Zhang, Chern Hui Lee, Ravi Kumar, K. J. Arnold, Stuart J. Masson, A. L. Grimsmo, A. S. Parkins, M. D. Barrett
Article
Optics
S. R. Chanu, V. P. W. Koh, K. J. Arnold, R. Kaewuam, T. R. Tan, Zhiqiang Zhang, M. S. Safronova, M. D. Barrett