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Published on: August 17, 2017
Conditional spin squeezing of a large ensemble via the vacuum Rabi splitting
Zilong Chen1, Justin G Bohnet, Shannon R Sankar
1JILA, University of Colorado, Boulder, Colorado 80309-0440, USA.
Abstract:
We use the vacuum Rabi splitting to perform quantum nondemolition measurements that prepare a conditionally spin squeezed state of a collective atomic psuedospin. 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) (87)Rb 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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