Takahiro Tow, a grad student in Prof. Amar Vutha's lab, has demonstrated the world's first cryogenic single-ion trap for an atomic clock. The device operates at 5 K, and traps one single Sr+ ion using electromagnetic fields. Synchronization of a laser's oscillating electric field to the Sr+ ion's quadrupole leads to a stable and accurate atomic clock. Operating the clock close to absolute zero freezes out all the thermal radiation that currently limits the accuracy of other single-ion clocks.

Image: The image shows the electrodes of the ion trap and a snapshot of a single Sr+ ion.
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