Advances in 133Cs Fountains: Control of the Cold Collision Shift and Observation of Feshbach Resonances
- BNM-SYRTE, Observatoire de Paris, 61 Avenue de l'Observatoire 75014 Paris (France)
- University of Western Australia, School of Physics, 35 Stirling Highway, Crawley, Western Australia (Australia)
- Laboratoire Kastler Brossel, ENS, 24 rue Lhomond 75005 Paris (France)
This paper describes the work performed at BNM-SYRTE (Observatoire de Paris) over the past few years toward the improvement and the use of microwave frequency standards using laser-cooled atoms. First, recent improvements of the 133Cs and 87Rb atomic fountains are described. An important advance is the achievement of a fractional frequency instability of 1.6 x 10-14{tau}-1/2 where {tau} is the measurement time in seconds, thanks to the routine use of a cryogenic sapphire oscillator as an ultra-stable local frequency reference. The second advance is a powerful method to control the frequency shift due to cold collisions. These two advances lead to a frequency stability of 2 x 10-16 at 50,000 s for the first time for primary standards. In addition, these clocks realize the SI second with an accuracy of 7 x 10-16, one order of magnitude below that of uncooled devices.
- OSTI ID:
- 20718894
- Journal Information:
- AIP Conference Proceedings, Vol. 770, Issue 1; Conference: ICAP 2004: 19. international conference on atomic physics, Rio de Janeiro (Brazil), 25-30 Jul 2004; Other Information: DOI: 10.1063/1.1928844; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Narrow 87Rb and 133Cs hyperfine transitions in evacuated wall-coated cells
Proposal of a truncated atomic beam fountain for reduction of collisional frequency shift