Hertz-Level Measurement of the Optical Clock Frequency in a Single 88Sr+ Ion

See allHide authors and affiliations

Science  19 Nov 2004:
Vol. 306, Issue 5700, pp. 1355-1358
DOI: 10.1126/science.1105497

You are currently viewing the abstract.

View Full Text


The frequency of the 5s 2S1/2–4d 2D5/2 electric quadrupole clock transition in a single, trapped, laser-cooled 88Sr+ ion has been measured by using an optical frequency comb referenced to a cesium fountain primary frequency standard. The frequency of the transition is measured as 444,779,044,095,484.6 (1.5) hertz, with a fractional uncertainty within a factor of 3 of that of the cesium standard. Improvements required to obtain a cesium-limited frequency measurement are described and are expected to lead to a 88Sr+ optical clock with stability and reproducibility exceeding that of the primary cesium standard.

View Full Text