Title :
Recent results on a pulsed CPT frequency standard
Author :
Dahes, F. ; Zanon, T. ; Guerandel, S. ; de Clerc, E. ; Dimarcq, N.
Author_Institution :
LNE-SYRTE, Paris, France
Abstract :
We recall recent results using pulsed interrogation CPT scheme and report a theoretical study of the hyperfine coherence relaxation rate which is a limitation to clock stability as well as continuous excitation or pulsed regime method. The hyperfine coherence relaxation of caesium in a cylindrical cell filled with buffer gas is plotted versus following experimental parameters: the sealing pressure, cell dimensions and temperature. The coherence relaxation is minimized at 41rad/s for a sealing pressure of 11 Torr, with a cell radius of 2 cm and a length of 10 cm. Then the collisional pressure shift of caesium is studied to evaluate impact of the second buffer gas introduced in the cell on the CPT frequency resonance shift.
Keywords :
atomic clocks; frequency standards; light coherence; radiation pressure; buffer gas; clock stability; coherent population trapping; continuous excitation; frequency resonance shift; hyperfine coherence relaxation rate; pulsed CPT frequency standard; pulsed interrogation CPT scheme; pulsed regime method; Atomic clocks; Atomic measurements; Coherence; Laser beams; Resonant frequency; Temperature measurement; Temperature sensors;
Conference_Titel :
Frequency and Time Forum (EFTF), 2006 20th European
Conference_Location :
Braunschweig
Print_ISBN :
978-1-4673-2642-1
