Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

National Conference on Laser Technology and Optoelectronics (LTO)

Performance evaluation of calcium atom beam vacuum system

Lu Zhang, Qingwen Xiao, Xing Chen, Junfeng Ge, Xiaobo Xue

Published Dec 2, 2020• 1 citation
Publisher

Abstract

Optical clocks have become a very important tool of investigating the characteristics of atoms or ions, for the state-of-art instability and uncertainty. Increasing the running time of an optical atomic clock is one critical issue that scientists are still working on. In this paper we report the improvement of the atomic chamber of a calcium beam optical clock. By using a combination of microtubes as the nozzle, we achieved a very high atomic flux with small divergence. The resonant atomic flux is about 1×1012 to 1013 per second and the divergence is smaller than 30mrad. The experimental results show that the system is reasonable in design and meets the technical indicators.

DOI
10.1117/12.2585357

Related papers

Atomic Beam Distribution in Calcium Beam Optical Clock

Lei Han, Xiaobo Xue, Hui Zhu +3 more

Optical clocks have become a very important tool of investigating the characteristics of atoms and ions, for the state-of-art instability and uncertainty. While optical clocks with long running time is still a critical issue. In order to improve vacuum system design and minimize atomic beam divergence angle in optical beam clock, the resonance fluorescence signal of the atom interacting with laser is adopted to evaluate atomic beam two-dimensional distribution. The laser frequency is stabilized to atomic transition resonance frequency via absorption spectrum method. Meanwhile, the laser beam fixed on a two-dimensional displacement platform is exploited to depict the atomic beam distribution with the resonance fluorescence intensity variation corresponding to each laser incident position. The experiment is carried on the calcium beam optical clock to obtain the preliminary atomic beam distribution.

Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)•May 15, 2023•0 citations

A small calcium beam optical frequency standard with fully-sealed vacuum tube

Haosen Shang, Xiaogang Zhang, Shengnan Zhang +2 more

In this paper a small Calcium beam optical frequency standard utilizing fully-sealed Calcium beam vacuum tube owning smaller size compared with vacuum system with flanges is demonstrated. Adopting the electron shelving detection method, we detect the clock transition 657 nm saturation absorbing spectroscopy whose linewidth is 500 kHz. The instability of this small optical frequency standard is 6.8×10-14at 1 second and 1.8×10-15after 1000 seconds of averaging by comparing with another small Calcium beam optical frequency standard whose reported instability is 3.0×10-14at 1 second. The optical part of the whole system is specially designed for robustness and miniaturization.

Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)•Jul 1, 2017•1 citation

Frequency shift properties of a calcium beam optical clock

Yu Chen, Yabei Su, Jiyang Ma +4 more

The optical frequency transitions with long-lifetime spin triplet states produced by the two valence electrons in the outermost layer of alkaline earth atoms make calcium atom a promising quantum frequency reference. Electron-shelving detection improves the signal-to-noise ratio of the clock transition spectrum, enabling a calcium atomic beam optical frequency standard. This scheme employs the 1S0-1P1 transition at 423 nm to detect the 1S0-3P1 transition at 657 nm, emphasizing the importance of 423 nm laser stability. While the performance of these clocks is well-studied, research on the atomic beam itself is limited. This study investigates frequency shifts in neutral calcium atoms’ 1S0-1P1 transition at 423 nm and their 1S0-3P1 transition at 657 nm. We measure the frequency shift caused by temperature, laser power, and laser alignment, providing insights to optimize the design of the calcium beam’s physical apparatus.

Frontiers in Physics•May 16, 2025•0 citations

Single-ion, transportable optical atomic clocks

Marion Delehaye, Clément Lacroûte

For the past 15 years, tremendous progress within the fields of laser stabilization, optical frequency combs and atom cooling and trapping have allowed the realization of optical atomic clocks with unrivaled performances. These instruments can perform frequency comparisons with fractional uncertainties well below 10-17, finding applications in fundamental physics tests, relativistic geodesy and time and frequency metrology. Even though most optical clocks are currently laboratory setups, several proposals for using these clocks for field measurements or within an optical clock network have been published, and most of time and frequency metrology institutes have started to develop transportable optical clocks. For the purpose of this special issue, we chose to focus on trapped-ion optical clocks. Even though their short-term fractional frequency stability is impaired by a lower signal-to-noise ratio, they offer a high potential for compactness: trapped ions demand low optical powers and simple loading schemes, and can be trapped in small vacuum chambers. We review recent advances on the clock key components, including ion trap and ultra-stable optical cavity, as well as existing projects and experiments which draw the picture of what future transportable, single-ion optical clocks may resemble.

arXiv:1804.02168•Journal of Modern Optics•Mar 7, 2018•42 citations

Miniaturized calcium beam optical frequency standard using fully-sealed vacuum tube with 10^−15 instability

Haosen Shang, Xiaogang Zhang, Shengnan Zhang +3 more

. To our knowledge, it's the first time to realize the optical frequency standard using fully-sealed vacuum tube. This work will promote the miniaturization and transportability of the optical clock based on atomic beam.

Optics Express•Nov 20, 2017•43 citations

An ion trap design for a space-deployable strontium-ion optical clock

Alessio Spampinato, Jonathan Stacey, Sean Mulholland +5 more

Optical atomic clocks demonstrate a better stability and lower systematic uncertainty than the highest performance microwave atomic clocks. However, the best performing optical clocks have a large footprint in a laboratory environment and require specialist skills to maintain continuous operation. Growing and evolving needs across several sectors are increasing the demand for compact robust and portable devices at this capability level. In this paper we discuss the design of a physics package for a compact laser-cooled 88 Sr + optical clock that would, with further development, be suitable for space deployment. We review the design parameters to target a relative frequency uncertainty at the low parts in 10 18 with this system. We then explain the results of finite-element modelling to simulate the response of the ion trap and vacuum chamber to vibration, shock and thermal conditions expected during launch and space deployment. Additionally, an electrostatic model has been developed to investigate the relationship between the ion trap geometrical tolerances and the trapping efficiency. We present the results from these analyses that have led to the design of a more robust prototype ready for experimental testing.

arXiv:2401.12706•Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences•Feb 1, 2024•7 citations
Optical clocks have become a very important tool of investigating the characteristics of atoms or ions, for the state-of-art instability and uncertainty. Increasing the running time of an optical atomic clock is one critical issue that scientists are still working on. In this paper we report the improvement of the atomic chamber of a calcium beam optical clock. By using a combination of microtubes as the nozzle, we achieved a very high atomic flux with small divergence. The resonant atomic flux is about 1×1012 to 1013 per second and the divergence is smaller than 30mrad. The experimental results show that the system is reasonable in design and meets the technical indicators.
Optical clocks have become a very important tool of investigating the characteristics of atoms and ions, for the state-of-art instability and uncertainty. While optical clocks with long running time is still a critical issue. In order to improve vacuum system design and minimize atomic beam divergence angle in optical beam clock, the resonance fluorescence signal of the atom interacting with laser is adopted to evaluate atomic beam two-dimensional distribution. The laser frequency is stabilized to atomic transition resonance frequency via absorption spectrum method. Meanwhile, the laser beam fixed on a two-dimensional displacement platform is exploited to depict the atomic beam distribution with the resonance fluorescence intensity variation corresponding to each laser incident position. The experiment is carried on the calcium beam optical clock to obtain the preliminary atomic beam distribution.
In this paper a small Calcium beam optical frequency standard utilizing fully-sealed Calcium beam vacuum tube owning smaller size compared with vacuum system with flanges is demonstrated. Adopting the electron shelving detection method, we detect the clock transition 657 nm saturation absorbing spectroscopy whose linewidth is 500 kHz. The instability of this small optical frequency standard is 6.8×10-14at 1 second and 1.8×10-15after 1000 seconds of averaging by comparing with another small Calcium beam optical frequency standard whose reported instability is 3.0×10-14at 1 second. The optical part of the whole system is specially designed for robustness and miniaturization.
The optical frequency transitions with long-lifetime spin triplet states produced by the two valence electrons in the outermost layer of alkaline earth atoms make calcium atom a promising quantum frequency reference. Electron-shelving detection improves the signal-to-noise ratio of the clock transition spectrum, enabling a calcium atomic beam optical frequency standard. This scheme employs the 1S0-1P1 transition at 423 nm to detect the 1S0-3P1 transition at 657 nm, emphasizing the importance of 423 nm laser stability. While the performance of these clocks is well-studied, research on the atomic beam itself is limited. This study investigates frequency shifts in neutral calcium atoms’ 1S0-1P1 transition at 423 nm and their 1S0-3P1 transition at 657 nm. We measure the frequency shift caused by temperature, laser power, and laser alignment, providing insights to optimize the design of the calcium beam’s physical apparatus.
For the past 15 years, tremendous progress within the fields of laser stabilization, optical frequency combs and atom cooling and trapping have allowed the realization of optical atomic clocks with unrivaled performances. These instruments can perform frequency comparisons with fractional uncertainties well below 10-17, finding applications in fundamental physics tests, relativistic geodesy and time and frequency metrology. Even though most optical clocks are currently laboratory setups, several proposals for using these clocks for field measurements or within an optical clock network have been published, and most of time and frequency metrology institutes have started to develop transportable optical clocks. For the purpose of this special issue, we chose to focus on trapped-ion optical clocks. Even though their short-term fractional frequency stability is impaired by a lower signal-to-noise ratio, they offer a high potential for compactness: trapped ions demand low optical powers and simple loading schemes, and can be trapped in small vacuum chambers. We review recent advances on the clock key components, including ion trap and ultra-stable optical cavity, as well as existing projects and experiments which draw the picture of what future transportable, single-ion optical clocks may resemble.
Optical atomic clocks demonstrate a better stability and lower systematic uncertainty than the highest performance microwave atomic clocks. However, the best performing optical clocks have a large footprint in a laboratory environment and require specialist skills to maintain continuous operation. Growing and evolving needs across several sectors are increasing the demand for compact robust and portable devices at this capability level. In this paper we discuss the design of a physics package for a compact laser-cooled 88 Sr + optical clock that would, with further development, be suitable for space deployment. We review the design parameters to target a relative frequency uncertainty at the low parts in 10 18 with this system. We then explain the results of finite-element modelling to simulate the response of the ion trap and vacuum chamber to vibration, shock and thermal conditions expected during launch and space deployment. Additionally, an electrostatic model has been developed to investigate the relationship between the ion trap geometrical tolerances and the trapping efficiency. We present the results from these analyses that have led to the design of a more robust prototype ready for experimental testing.