Title :
The CSIRO trapped 171Yb+ ion clock: improved accuracy through laser-cooled operation
Author :
Warrington, R. Bruce ; Fisk, Peter T H ; Wouters, Michael J. ; Lawn, Malcolm A. ; Coles, Colin
Author_Institution :
Nat. Meas. Lab., CSIRO, Lindfield, NSW, Australia
Abstract :
The microwave frequency standard based on buffer gas-cooled 171Yb+ ions at the CSIRO National Measurement Laboratory has demonstrated high stability, but has an accuracy limited by the second-order Doppler shift due to the thermal motion of the ions. We report measurements obtained with a cloud of approximately 104 ions laser-cooled to below 1 K, including near shot noise-limited Ramsey fringes with a pulse separation up to 10 s. Estimates indicate that a potential stability of σy(τ)=5×10-14 τ-1/2 and a total uncertainty of 5 parts in 1015 or better are achievable for this system
Keywords :
Doppler shift; atom-photon collisions; atomic clocks; frequency standards; laser cooling; microwave measurement; microwave spectra; particle traps; positive ions; quantum optics; radiation pressure; shot noise; trapped ions; ytterbium; 1 K; 10 s; 171Yb+ ion clock; 171Yb+ ions; CSIRO National Measurement Laboratory; CSIRO ion clock; Yb; buffer gas-cooled ions; laser-cooled ions; laser-cooled operation; microwave frequency standard; potential stability; pulse separation; second-order Doppler shift; shot noise-limited Ramsey fringes; thermal motion; total uncertainty; Doppler shift; Frequency measurement; Laboratories; Measurement standards; Microwave frequencies; Microwave measurements; Motion measurement; Noise measurement; Pulse measurements; Thermal stability;
Conference_Titel :
Frequency and Time Forum, 1999 and the IEEE International Frequency Control Symposium, 1999., Proceedings of the 1999 Joint Meeting of the European
Conference_Location :
Besancon
Print_ISBN :
0-7803-5400-1
DOI :
10.1109/FREQ.1999.840724
