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arXiv · 1909.07524

A cavity-QED protocol for precise field sensing in the optical domain

Robert J. Lewis-Swan·D. Barberena·Juan A. Muniz·Julia R. K. Cline·Dylan Young·James K. Thompson·Ana Maria Rey
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Abstract

In the context of quantum metrology, optical cavity-QED platforms have primarily been focused on the generation of entangled atomic spin states useful for next-generation frequency and time standards. Here, we report a complementary application: The use of optical cavities to generate non-classical states of light for electric field sensing below the standard quantum limit. We show that cooperative atom-light interactions in the strong collective coupling regime can be used to engineer generalized atom-light cat states which enable quantum enhanced sensing of small displacements of the cavity field even in the presence of photon loss. We demonstrate that metrological gains of 10-20 dB below the standard quantum limit are within reach for current cavity-QED systems operating with long-lived alkaline-earth atoms.

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Robert J. Lewis-Swan, D. Barberena, Juan A. Muniz, Julia R. K. Cline, Dylan Young, James K. Thompson, Ana Maria Rey. 2019-09-16. A cavity-QED protocol for precise field sensing in the optical domain. https://doi.org/10.1103/physrevlett.124.193602

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