Title :
Progress at NIST toward absolute frequency standards using stored ions
Author :
Wineland, D.J. ; Bergquist, J.C. ; Bollinger, J.J. ; Itano, W.M. ; Heinzen, D.J. ; Gilbert, S.L. ; Manney, C.H. ; Raizen, M.G.
Author_Institution :
Nat. Inst. of Stand. & Technol., Boulder, CO, USA
Abstract :
Experiments directed toward the realization of frequency standards of high accuracy using stored ions are briefly summarized. In one experiment, an RF oscillator is locked to a nuclear spin-flip hyperfine transition (frequency approximately= 3.03*10/sup 8/ Hz) in /sup 9/Be/sup +/ ions that are stored in a Penning trap and sympathetically laser-cooled. Stability is better than 3*10/sup -12/ tau /sup -(1/2)/ and uncertainty in Doppler shifts is estimated to be less than 5*10/sup -15/. In a second experiment, a stable laser is used to probe an electric quadrupole transition (frequency approximately=1.07*10/sup 15/ Hz) in a single laser-cooled /sup 199/Hg/sup +/ ion stored in a Paul trap. The measured Q value of this transition is approximately 10/sup 13/. Future possible experiments are discussed.<>
Keywords :
frequency measurement; measurement standards; particle traps; 1.07*10/sup 5/ Hz; 3.03*10/sup 8/ Hz; Be ions; Doppler shifts; Hg ions; Paul trap; Penning trap; Q value; RF oscillator; absolute frequency standards; electric quadrupole transition; laser cooled ions; nuclear spin-flip hyperfine transition; stored ions; Doppler shift; Laser stability; Laser transitions; Mercury (metals); NIST; Oscillators; Probes; Radio frequency; Resonant frequency; Uncertainty;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
