VISUAL ARCHIVE / IMAGE STORY
The Loop That Makes a Clock Run
Absorption changes become a correction to a drifting laser.
The crucial step is feedback. When the driving laser begins to drift away from the thorium-229 resonance, the nuclear response changes. That information can be fed back into the system so the laser is continually pulled toward the frequency set by the nucleus. Illustration: The Last Transmission.
THE OBSERVATION
What we can actually see.
A continuous-wave laser is steered toward the thorium transition using rapid feedback based on absorption spectroscopy. The team compared a subharmonic against a ytterbium-ion clock during continuous operation.
THE ILLUSTRATION
What the artwork imagines.
The visible arrows and instant correction dramatize a control signal. The picture is not an oscilloscope trace, and one successful loop does not imply record-setting clock performance.
FROM THE ILLUSTRATED ARTICLE
The story that inspired it.
The article traces the path from thorium-229 spectroscopy to a laser kept on a nuclear transition by feedback. Absorption changes become a correction to a drifting laser.
Read The First Nuclear Clock Has Started TickingCHECK THE RECORD
The image interprets the research below. Follow the original work for the measurements and limits behind the scene.
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