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arXiv · 0912.3895

Entanglement-assisted atomic clock beyond the projection noise limit

Anne Louchet-Chauvet·Jürgen Appel·Jelmer J. Renema·Daniel Oblak·Niels Kjærgaard·Eugene S. Polzik
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Abstract

We use a quantum non-demolition measurement to generate a spin squeezed state and to create entanglement in a cloud of 10^5 cold cesium atoms, and for the first time operate an atomic clock improved by spin squeezing beyond the projection noise limit in a proof-of-principle experiment. For a clock-interrogation time of 10 μ\s the experiments show an improvement of 1.1 dB in the signal-to-noise ratio, compared to the atomic projection noise limit.

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Anne Louchet-Chauvet, Jürgen Appel, Jelmer J. Renema, Daniel Oblak, Niels Kjærgaard, Eugene S. Polzik. 2010-03-21. Entanglement-assisted atomic clock beyond the projection noise limit. https://doi.org/10.1088/1367-2630%2F12%2F6%2F065032

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