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arXiv · 1103.0335

Conditional Spin-Squeezing of a Large Ensemble via the Vacuum Rabi Splitting

Zilong Chen·Justin G. Bohnet·Shannon R. Sankar·Jiayan Dai·James K. Thompson
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Abstract

We use the vacuum Rabi splitting to perform quantum nondemolition (QND) measurements that prepare a conditionally spin-squeezed state of a collective atomic psuedo-spin. We infer a 3.4(6) dB improvement in quantum phase estimation relative to the standard quantum limit for a coherent spin state composed of uncorrelated atoms. The measured collective spin is composed of the two-level clock states of nearly 10^6 Rb-87 atoms confined inside a low finesse F = 710 optical cavity. This technique may improve atomic sensor precision and/or bandwidth, and may lead to more precise tests of fundamental physics.

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Zilong Chen, Justin G. Bohnet, Shannon R. Sankar, Jiayan Dai, James K. Thompson. 2011-03-02. Conditional Spin-Squeezing of a Large Ensemble via the Vacuum Rabi Splitting. https://doi.org/10.1103/physrevlett.106.133601

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