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

Laser Physics

Comparative short-term stability for a Cs beam and an expanding cold atomic cloud of Cs used as atomic frequency standards

Daniel Varela Magalhães, Stella Müller, Aida Bebeachibuli, Renato Ferracini Alves, Vanderlei Salvador Bagnato

Published Aug 1, 2006• 4 citations
Publisher

Abstract

We have compared the stability of two distinct atomic frequency standards. One is based on an atomic cold cloud of 133 Cs atoms in free expansion, interrogated by a Rabi resonance. The other standard is based on a thermal Cs beam interrogated by the separated oscillatory field method (Ramsey’s method). The atomic expanding cloud standard shows better stability and technical advances based on its simplicity.

DOI
10.1134/s1054660x06080160

Related papers

Free expanding cloud of cold atoms as an atomic standard: Ramsey fringes contrast

Stella Müller, Daniel Varela Magalhães, Aida Bebeachibuli +3 more

A compact frequency standard based on an expanding cold Cs133 cloud is under development in our laboratory. In a first experiment, Cs cold atoms were prepared by a magneto-optical trap in a vapor cell, and a microwave antenna was used to transmit the radiation for the clock transition. The signal obtained from fluorescence of the expanding cold atoms cloud is used to lock a microwave chain. In this way the overall system stability is evaluated. A theoretical model based on a two-level system interacting with the two microwave pulses enables interpretation for the observed features, especially the poor Ramsey fringes contrast.

Journal of the Optical Society of America B•May 14, 2008•9 citations

Demonstration and Observation of a Frequency Standard Based on an Expanding Cold Atoms Cloud of Cesium

Stella Müller, Daniel Varela Magalhães, Aida Bebeachibuli +2 more

This work reports the first results obtained in a laboratory system implemented to be a primary standard based on an expanding cloud of cold 133Cs. An atomic sample is prepared through the magneto-optical trapping technique, and after the loading procedure the atomic cloud is left to freely expand. A microwave interrogation signal is applied to the atoms, probing them in the ground state transition 6S1/2(F = 3)- 6S1/2(F = 4). The microwave interrogation was applied either in one or two pulses methods. The system could be also locked in a commercial standard to perform its stability evaluation. The first results showed a stability of 9times10-11tau-frac12, promising for such use of simple type of frequency standard

Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)•Jan 18, 2006•3 citations

Compact frequency standard based on an intracavity sample of cold cesium atoms

Stella Müller, Daniel Varela Magalhães, Renato Ferracini Alves +1 more

We have demonstrated the possibility for a compact frequency standard based on a sample of cold cesium atoms. In a cylindrical microwave cavity, the atoms are cooled and interrogated during a free expansion and then detected. The operation of this experiment is different from conventional atomic fountains since all the steps are sequentially performed in the same position of space. In this paper we report the analysis of a Ramsey pattern observed to present a (47±5) Hz linewidth and a stability of (5±0.5)x10−13τ−1/2 for an integration time longer than 100 s. Some of the main limitations of the standard are analyzed. This present report demonstrates considerable improvement of our previous work [J. Opt. Soc. Am. B25, 909 (2008)JOBPDE0740-322410.1364/JOSAB.25.000909] where the atoms were in a free space and not inside a microwave cavity.

Journal of the Optical Society of America B•Oct 5, 2011•39 citations

Compact Frequency Standard Based on an Intra-cavity Sample Cold Cesium Atoms

Stella Müller, Daniel Varela Magalhães, Renato Ferracini Alves +1 more

We have demonstrated the possibility for a compact frequency standard based on a sample of cold cesium atoms. In a cylindrical microwave cavity, the atoms are cooled and interrogated during a free expansion and then detected. The operation of this experiment is different from conventional atomic fountains, since all the steps are sequentially performed in the same position of space. In this paper we report the analysis of a Ramsey pattern observed to present a 47 Hz linewidth and a stability of 5x10^-13 for an integration time longer than 100s. Some of the main limitations of the standard are analyzed. This present report demonstrates considerable improvement of our previous work (S. T. Muller et al, J. Opt. Soc. Am. B, v.25, p.909, 2008) where the atoms were in a free space and not inside a microwave cavity.

arXiv:1108.4407•Aug 22, 2011•0 citations

Raman–Ramsey Interaction for Coherent Population Trapping Cs Clock

Stéphane Guérandel, T. Zanon-Willette, N. Castagna +4 more

A gas cell atomic frequency standard based on coherent population trapping (CPT) with Ramsey interrogation pulses is developed. The clock resonance is detected in a Cs cell with buffer gas using two phase-locked diode lasers tuned to the D1 line. A preliminary short-term stability of$3.5 \times 10^{-12}t^{-1/2}$is reported. The CPT specificity allows a new interrogation–detection sequence, i.e., the continuous pulse train, which, with phase modulation, could lead to better short-term stability compared to usual continuous CPT clocks. The parameters optimizing the stability include a high Rabi frequency, a very short measurement time, and an interrogation time equal to the lifetime of the hyperfine coherence.

IEEE Transactions on Instrumentation and Measurement•Mar 16, 2007•43 citations

Development of a Mobile Atomic Frequency Standard based on Cold Atoms

Stella Müller, Felipe Arduini Otoboni, Jair de Martin +3 more

We have been developing a compact frequency standard based on cold cesium atoms. The atoms are cooled, interrogated during a free expansion and then detected inside a cylindrical microwave cavity. The operation of this experiment is different from conventional cold atoms fountains, since all the steps are sequentially performed in the same place.

Latin America Optics and Photonics Conference•Jan 1, 2012•3 citations
We have compared the stability of two distinct atomic frequency standards. One is based on an atomic cold cloud of 133 Cs atoms in free expansion, interrogated by a Rabi resonance. The other standard is based on a thermal Cs beam interrogated by the separated oscillatory field method (Ramsey’s method). The atomic expanding cloud standard shows better stability and technical advances based on its simplicity.
A compact frequency standard based on an expanding cold Cs133 cloud is under development in our laboratory. In a first experiment, Cs cold atoms were prepared by a magneto-optical trap in a vapor cell, and a microwave antenna was used to transmit the radiation for the clock transition. The signal obtained from fluorescence of the expanding cold atoms cloud is used to lock a microwave chain. In this way the overall system stability is evaluated. A theoretical model based on a two-level system interacting with the two microwave pulses enables interpretation for the observed features, especially the poor Ramsey fringes contrast.
This work reports the first results obtained in a laboratory system implemented to be a primary standard based on an expanding cloud of cold 133Cs. An atomic sample is prepared through the magneto-optical trapping technique, and after the loading procedure the atomic cloud is left to freely expand. A microwave interrogation signal is applied to the atoms, probing them in the ground state transition 6S1/2(F = 3)- 6S1/2(F = 4). The microwave interrogation was applied either in one or two pulses methods. The system could be also locked in a commercial standard to perform its stability evaluation. The first results showed a stability of 9times10-11tau-frac12, promising for such use of simple type of frequency standard
We have demonstrated the possibility for a compact frequency standard based on a sample of cold cesium atoms. In a cylindrical microwave cavity, the atoms are cooled and interrogated during a free expansion and then detected. The operation of this experiment is different from conventional atomic fountains since all the steps are sequentially performed in the same position of space. In this paper we report the analysis of a Ramsey pattern observed to present a (47±5) Hz linewidth and a stability of (5±0.5)x10−13τ−1/2 for an integration time longer than 100 s. Some of the main limitations of the standard are analyzed. This present report demonstrates considerable improvement of our previous work [J. Opt. Soc. Am. B25, 909 (2008)JOBPDE0740-322410.1364/JOSAB.25.000909] where the atoms were in a free space and not inside a microwave cavity.
We have demonstrated the possibility for a compact frequency standard based on a sample of cold cesium atoms. In a cylindrical microwave cavity, the atoms are cooled and interrogated during a free expansion and then detected. The operation of this experiment is different from conventional atomic fountains, since all the steps are sequentially performed in the same position of space. In this paper we report the analysis of a Ramsey pattern observed to present a 47 Hz linewidth and a stability of 5x10^-13 for an integration time longer than 100s. Some of the main limitations of the standard are analyzed. This present report demonstrates considerable improvement of our previous work (S. T. Muller et al, J. Opt. Soc. Am. B, v.25, p.909, 2008) where the atoms were in a free space and not inside a microwave cavity.
A gas cell atomic frequency standard based on coherent population trapping (CPT) with Ramsey interrogation pulses is developed. The clock resonance is detected in a Cs cell with buffer gas using two phase-locked diode lasers tuned to the D1 line. A preliminary short-term stability of3.5×10−12t−1/23.5 \times 10^{-12}t^{-1/2}3.5×10−12t−1/2is reported. The CPT specificity allows a new interrogation–detection sequence, i.e., the continuous pulse train, which, with phase modulation, could lead to better short-term stability compared to usual continuous CPT clocks. The parameters optimizing the stability include a high Rabi frequency, a very short measurement time, and an interrogation time equal to the lifetime of the hyperfine coherence.