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arXiv · 0901.2585

Bayesian estimation in homodyne interferometry

Stefano Olivares·Matteo G. A. Paris
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Abstract

We address phase-shift estimation by means of squeezed vacuum probe and homodyne detection. We analyze Bayesian estimator, which is known to asymptotically saturate the classical Cramer-Rao bound to the variance, and discuss convergence looking at the a posteriori distribution as the number of measurements increases. We also suggest two feasible adaptive methods, acting on the squeezing parameter and/or the homodyne local oscillator phase, which allow to optimize homodyne detection and approach the ultimate bound to precision imposed by the quantum Cramer-Rao theorem. The performances of our two-step methods are investigated by means of Monte Carlo simulated experiments with a small number of homodyne data, thus giving a quantitative meaning to the notion of asymptotic optimality.

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Stefano Olivares, Matteo G. A. Paris. 2009-02-16. Bayesian estimation in homodyne interferometry. https://doi.org/10.1088/0953-4075/42/5/055506

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