The mercury ion optical clock

Sunday, July 16 2006 @ 10:35 PM PDT

From 2002-2005 I worked in the NIST Time and Frequency division on a next-generation atomic clock. The clock is based on a single trapped mercury atom. The most significant result of my work on the clock was a dramatic improvement in its precision, and the report on this progress was finally published this week. The NIST Press Release compares the accuracy of the mercury clock to the NIST-F1 cesium fountain standard: "The current version of NIST-F1—if it were operated continuously—would neither gain nor lose a second in about 70 million years. The latest version of the mercury clock would neither gain nor lose a second in about 400 million years." Read an article from Science News about the paper, or one from Seed Magazine.

The article published this week appeared in Physical Review Letters. You can actually read the paper here, redistributed by NIST. There has been a little bit of press and web coverage of this result, although it mostly seems to be derived directly from the press release.

• Chem Exec
• Rocky Mountain News
• USA Today
• Digg (and again), where the LED Dining Table is more interesting than atomic clocks
• ZDNet
• Engadget
• InformationWeek
• Dvorak Uncensored
• Physorg
• eetimes
• Daily Tech

NIST, the National Institute of Standards and Technology. is a US Department of Commerce agency formerly known as the National Bureau of Standards.

The image shown here is a cut-away drawing of the cryogenic vacuum chamber system that holds the mercury ion trap. The two tanks of liquid are liquid nitrogen (top) and helium (bottom). The ion trap itself is located in the lowest part of the drawing, a large copper cylinder. I made the drawing in POV-Ray.

Technorati tags: clocks, atomic clock, science, physics, ion, mercury

Comments (3)

Evil Mad Scientist Laboratories
http://www.evilmadscientist.com/article.php/HgClock