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arXiv · 2205.09698

Quantum-enhanced differential atom interferometers and clocks with spin-squeezing swapping

Robin Corgier·Marco Malitesta·Augusto Smerzi·Luca Pezzè
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Abstract

Thanks to common-mode noise rejection, differential configurations are crucial for realistic applications of phase and frequency estimation with atom interferometers. Currently, differential protocols with uncorrelated particles and mode-separable settings reach a sensitivity bounded by the standard quantum limit (SQL). Here we show that differential interferometry can be understood as a distributed multiparameter estimation problem and can benefit from both mode and particle entanglement. Our protocol uses a single spin-squeezed state that is mode-swapped among common interferometric modes. The mode swapping is optimized to estimate the differential phase shift with sub-SQL sensitivity. Numerical calculations are supported by analytical approximations that guide the optimization of the protocol. The scheme is also tested with simulation of noise in atomic clocks and interferometers.

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Robin Corgier, Marco Malitesta, Augusto Smerzi, Luca Pezzè. 2022-05-19. Quantum-enhanced differential atom interferometers and clocks with spin-squeezing swapping. https://doi.org/10.22331/q-2023-03-30-965

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