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arXiv · 2003.10943

Heisenberg-limited noisy atomic clock using a hybrid coherent and squeezed states protocol

Luca Pezzè·Augusto Smerzi
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Abstract

We propose a hybrid quantum-classical atomic clock protocol where the interrogation of an ensemble of uncorrelated atoms in a spin-coherent state is used to feedback one (or more) spin-squeezed atomic ensembles toward their optimal phase sensitivity point. This protocol overcomes the stability of a single Ramsey clock and it reaches a Heisenberg-limited stability while avoiding non-destructive measurements. Analytical predictions are compared with numerical simulations of clocks operations including correlated 1/f local oscillator noise.

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Luca Pezzè, Augusto Smerzi. 2020-03-24. Heisenberg-limited noisy atomic clock using a hybrid coherent and squeezed states protocol. https://doi.org/10.1103/physrevlett.125.210503

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