Flaws in diamond crystals could make precise timekeeping more convenient.

Today's most accurate timekeeping standards are kept by clocks that contain hard-to-manufacture atomic gases. These clocks are usually placed only in specialist laboratories or on satellites, where their signals are used for applications such as communication and navigation. Dirk Englund, now at Massachusetts Institute of Technology in Cambridge, and his colleagues propose a scheme for keeping time using a diamond containing a nitrogen impurity. This defect has an oscillating electronic spin state that could be detected from the light it emits when excited by a laser, and therefore could provide a timekeeping signal. A device that relies on diamond chips would be more portable than atomic clocks, as well as easier to integrate into solid-state manufacturing.

Phys. Rev. A 87, 032118 (2013)