Applied Physics

A Miniature Clock Factory

See allHide authors and affiliations

Science  30 Sep 2005:
Vol. 309, Issue 5744, pp. 2138
DOI: 10.1126/science.309.5744.2138d

The combination of developments in microfabrication and precision spectroscopy of confined atomic gases has promised to benefit applications in timing metrology, where the requirements of low cost and small size along with long-term stability are paramount. However, earlier work on chip-sized atomic clocks has shown that chemical reactions in the gas cell, resulting from the presence of impurities and byproduct gases from the cell fabrication and gas-filling processes, lead to long-term drift in the clock frequency.

Knappe et al.have devised a fabrication and cell-filling technique that removes much of the contaminant gas from the cell, and they show that the frequency stability can be improved by several orders of magnitude to a drift of no more than 5 × 10−11 per day. The improvement suggests chip-scale atomic clocks as a viable technology in applications where better precision than that available in quartz-based clocks is desired. — ISO

Opt. Lett. 30, 2351 (2005).

Navigate This Article