By Topic

Analysis tools for the accurate evaluation of a small frequency standard

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
Hamouda, F. ; Lab. de l''Horloge Atom., Univ. de Paris-Sud, Orsay, France ; Theobald, G. ; Cerez, Pierre ; Audoin, Claude

The short, optically pumped cesium beam tube developed at Laboratoire de l'Horloge Atomique has been carefully evaluated. For that purpose, we have developed a digital servo system that controls three parameters: the frequency of the ultra stable oscillator (USO), the microwave power of the signal experienced by the cesium atoms, and the static magnetic field applied to the atoms. The frequency standard shows a very satisfactory level of short- and medium-term frequency stabilities. A relative frequency offset, measured to be 4.10/sup -12/, results mainly from the residual phase difference between the oscillatory fields in the two interaction regions, which is due to imperfection in cavity symmetry. We present two different means of analyzing the causes of this spurious frequency offset using theoretical and experimental considerations. First, a numerical simulation of the beam tube response is performed as a function of the microwave field amplitude for different values of the residual phase difference /spl Delta//spl Phi/. Results include the cavity-pulling effect. Compared with the measured frequency offset, the numerical simulation leads to a second-order Doppler shift of -3.3 mHz and a residual phase difference, /spl Delta//spl Phi/, between the fields interacting with the atoms in the second and first regions of the Ramsey cavity, amounting to +150 /spl mu/rad. Second, an experimental method of measurement of /spl Delta//spl Phi/ without beam reversal is implemented. The latter yields /spl Delta//spl Phi/=155/spl plusmn/17 /spl mu/rad. Finally, the clock accuracy is determined. It is equal to /spl plusmn/14.10/sup -13/.

Published in:

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on  (Volume:47 ,  Issue: 2 )