First performance results of PTB's atomic caesium fountain and a study of contributions to its frequency instability

S Weyers; A Bauch; U Hubner; R Schroder; C Tamm

doi:10.1109/58.827431

First performance results of PTB's atomic caesium fountain and a study of contributions to its frequency instability

IEEE Trans Ultrason Ferroelectr Freq Control. 2000;47(2):432-7. doi: 10.1109/58.827431.

Authors

S Weyers¹, A Bauch, U Hubner, R Schroder, C Tamm

Affiliation

¹ Phys. Tech. Bundesanstalt, Braunschweig.

PMID: 18238561
DOI: 10.1109/58.827431

Abstract

At the Physikalisch-Technische Bundesanstalt (PTB), an atomic caesium fountain was constructed. Ramsey fringes with a full width at half maximum (FWHM) of 0.86 Hz were obtained by launching the atoms to a height of 83 cm above the cooling region (40 cm above the microwave cavity center). A first measurement of the homogeneity of the magnetic flux density yields 0.33 nT (rms), only 0.16% of the mean value of 0.205 muT used in normal operation. The inherent elementary noise contributions of the fountain and of a thermal beam atomic clock are compared in some detail.