Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)

MOT-based continuous cold Cs-beam atomic clock

Haijin Wang, Gebriel H. Iyanu

Published Jun 1, 2010• 5 citations

Publisher

Abstract

In this paper we report our design and experimental results towards demonstration of a magneto optical trap (MOT)-based cold Cs-beam atomic clock. We generated a continuous cold Cs beam from a Cs MOT by perturbing the MOT potential and measured the longitudinal velocity of the Cs beam to be 7 m/s. In order to separate the atomic beam from the MOT laser beam, we used a one-dimensional optical molasses to deflect the Cs beam through an angle of 30° before the atomic beam enters the microwave cavity. Our Cs beam has an instantaneous atomic flux of 3.6 × 1010atoms/s when operated in pulsed mode and a continuous flux of 2 × 108atoms/s. Under current experimental conditions, the observed cold Cs atomic beam parameters infer a short-term, shot-noise limited Allan standard deviation of 2.7 × 10-13τ-1/2(τ is the averaging time) for the cold Cs beam clock under development.

DOI: 10.1109/freq.2010.5556290

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