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Physical Review A

Bayesian estimation of differential interferometer phase

John K. Stockton, Xinan Wu, Mark A. Kasevich

Published Sep 19, 2007• 80 citations
Publisher

Abstract

We apply Bayesian logic to optimally estimate the differential phase in a discrete-time, dual-interferometer measurement. This method is particularly relevant to the case of a gravity gradiometer, where the gravity gradient between cold-atom fountain interferometers can be estimated from the differential phase, despite the presence of large common phase (acceleration) fluctuations. Given an accurate model, the bias-free algorithm we present is optimal and leverages experimental knowledge of the system noise, classical or quantum, to outperform other typical estimators, including ellipse-fitting techniques.

DOI
10.1103/physreva.76.033613

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