Troisième Symposium sur les Etalons de Fréquence et la Métrologie / Third Symposium on Frequency Standards and Metrology

J. Phys. Colloques 42 (1981) C8-3-C8-14
DOI: 10.1051/jphyscol:1981801

RAMSEY FRINGES USING TRANSITIONS IN THE VISIBLE AND 10 µm SPECTRAL REGIONS : EXPERIMENTAL METHODS

Ch. Salomon¹, Ch. Bréant¹, Ch. J. Bordé¹ et R.L. Barger<sup>2, 3

1</sup>  Laboratoire de Physique des Lasers, associé au C.N.R.S. n° 282, Université Paris-Nord, F-93430 Villetaneuse, France
²  Laseangle, Inc., Rollinsville, Colorado 80474, U. S. A. and Laboratoire de Physique des Lasers, Université Paris-Nord, F-93430 Villetaneuse, France
³  The research on Ca was done while this author was a member of the National Bureau of Standards, Boulder, Colorado.

Abstract
A description is given of the experimental system which was used for obtaining Ramsey fringes with an atomic beam for the Ca 657 nm line, and for the system which is being set up to obtain fringes with a large absorption cell for various molecules in the 10 µm region. Details of the cat's eye and segmented retroreflector optical systems are discussed. Results obtained with Ca include fringe widths as small as 1 kHz HWHM, resolution of the recoil splitting, and resolution of second-order Doppler broadening and shift. The experiment at 10 µm is in progress and has already yielded a 1.25 kHz linewidth (HWHM) for the single zone signal with the SF₆ molecule.