Title :
Recent stability comparisons with the JPL linear trapped ion frequency standards
Author :
Tjoelker, R.L. ; Prestage, J.D. ; Dick, G.J. ; Maleki, L.
Author_Institution :
Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA
Abstract :
The 199Hg+ research frequency standards LITS-1 and LITS-2 were developed to provide continuous, reliable, high stability performance. For simplicity, a 202Hg lamp is used for state selection and a helium buffer gas for ion cooling. In a preliminary 9 day comparison between the trapped ion standards, the Allan deviation was σy(τ)=1×10-13/τ1/2 and a fractional frequency stability of 6×10-16 measured for averaging times greater than 105 seconds. A 40 day comparison of LITS-2 against an auto-tuned H-maser referenced to UTC-NIST puts an upper limit on long term drift of LITS-2 of 1.2(1.4)×10-16/day
Keywords :
frequency measurement; frequency stability; hyperfine structure; measurement standards; mercury (metal); particle traps; trapped ions; 105 s; 40 day; 9 d; 199Hg+ frequency standards; 202Hg lamp; Hg; JPL linear trapped ion frequency standards; LITS-1; LITS-2; UTC-NIST; auto-tuned H-maser; fractional frequency stability; helium buffer gas; ion cooling; long term drift; stability comparisons; Frequency; Laboratories; Lamps; Local oscillators; Masers; Optical buffering; Propulsion; Stability; Standards development; Superconducting device noise;
Conference_Titel :
Frequency Control Symposium, 1994. 48th., Proceedings of the 1994 IEEE International
Conference_Location :
Boston, MA
Print_ISBN :
0-7803-1945-1
DOI :
10.1109/FREQ.1994.398254
