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Progress on a portable rubidium fountain frequency standard



Paul D. Kunz, Thomas P. Heavner, Steven R. Jefferts


We are developing a simple and transportable laser-cooled rubidium (Rb) atomic fountain frequency standard. The optical package for this system uses DFB (distributed feedback) diode lasers and a frequency offset locking scheme to generate the optical frequencies needed for laser-cooling, launching, post-cooling, and detection of Rb atoms. This atomic fountain will be useful as a transfer-standard and secondary standard for calibrating nontransportable frequency standards, as well as a measurement tool for the gravitational red-shift. Here we describe the progress made on this project, including our recent observation of a magneto-optical trap (MOT), and the anticipated performance of our transportable Rb fountain frequency standard.
Proceedings Title
Proc. 2008 PTTI Conf.
Conference Dates
December 1-5, 2008
Conference Location
Reston, VA


atomic clock, frequency standard, laser cooling, rubidium


Kunz, P. , Heavner, T. and Jefferts, S. (2008), Progress on a portable rubidium fountain frequency standard, Proc. 2008 PTTI Conf., Reston, VA, [online], (Accessed June 24, 2024)


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Created December 1, 2008, Updated February 19, 2017