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arXiv · 1508.05129

Probing beyond the laser coherence time in optical clock comparisons

David B. Hume·David R. Leibrandt
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Abstract

We develop differential measurement protocols that circumvent the laser noise limit in the stability of optical clock comparisons by synchronous probing of two clocks using phase-locked local oscillators. This allows for probe times longer than the laser coherence time, avoids the Dick effect, and supports Heisenberg-limited measurement precision. We present protocols for such frequency comparisons and develop numerical simulations of the protocols with realistic noise sources. These methods provide a route to reduce frequency ratio measurement durations by more than an order of magnitude.

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David B. Hume, David R. Leibrandt. 2016-04-12. Probing beyond the laser coherence time in optical clock comparisons. https://doi.org/10.1103/physreva.93.032138

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