Eur. Phys. J. D 33, 173-179 (2005)
https://doi.org/10.1140/epjd/e2005-00064-2

Noise sensitivity of an atomic velocity sensor

Theoretical and experimental treatment

¹ Laboratoire Kastler Brossel, École Normale Supérieure, CNRS, UPMC, 4 place Jussieu, 75252 Paris Cedex 05, France
² CNAM-INM, Conservatoire National des Arts et Métiers, 292 rue Saint Martin, 75141 Paris Cedex 03, France

Corresponding author: ^a guellati@spectro.jussieu.fr

Received: 26 October 2004
Revised: 7 January 2005
Published online: 3 May 2005

Abstract

We use Bloch oscillations to accelerate coherently rubidium atoms. The variation of the velocity induced by this acceleration is an integer number times the recoil velocity due to the absorption of one photon. The measurement of the velocity variation is achieved using two velocity selective Raman π-pulses: the first pulse transfers atoms from the hyperfine state , to , into a narrow velocity class. After the acceleration of this selected atomic slice, we apply the second Raman pulse to bring the resonant atoms back to the initial state , . The populations in (F=1 and F=2) are measured separately by using a one-dimensional time-of-flight technique. To plot the final velocity distribution we repeat this procedure by scanning the Raman beam frequency of the second pulse. This two π-pulses system constitutes then a velocity sensor. Any noise in the relative phase shift of the Raman beams induces an error in the measured velocity. In this paper we present a theoretical and an experimental analysis of this velocity sensor, which take into account the phase fluctuations during the Raman pulses.