The world’s smallest atomic clock has been built at NIST in Boulder, Colorado. About the size of a rice grain (see photo), the clock is built around a semiconductor laser, micro-optics, a heater, and a microcell filled with cesium atoms. Using only 73 mW of electrical power, the clock has a precision of 2.5 × 10−10 over 1 second and 2.5 × 10−11 over 250 seconds. Far more precise clocks are available—some are good to about one part in 1015—but they can require a large tabletop’s worth of equipment. This new, tiny, low-power, high-precision clock is also likely to be cheap; it uses standard microfabrication techniques whereby the same process sequence can make thousands of the physics packages on silicon wafers. The timekeeper could be used, for example, in a variety of hand-held, battery-operated devices. (S. Knappe et al. , Appl. Phys. Lett. 85 ,...
Skip Nav Destination
Article navigation
1 October 2004
October 01 2004
Citation
Philip F. Schewe; The world’s smallest atomic clock. Physics Today 1 October 2004; 57 (10): 9. https://doi.org/10.1063/1.2408602
Download citation file:
PERSONAL SUBSCRIPTION
Purchase an annual subscription for $25. A subscription grants you access to all of Physics Today's current and backfile content.
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
82
Views
Citing articles via
The lessons learned from ephemeral nuclei
Witold Nazarewicz; Lee G. Sobotka
FYI science policy briefs
Lindsay McKenzie; Jacob Taylor