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arXiv · 1904.00557

Multi-outcome homodyne detection in a coherent-state light interferometer

J. Z. Wang·Z. Q. Yang·A. X. Chen·W. Yang·G. R. Jin
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Abstract

The Cramér-Rao bound plays a central role in both classical and quantum parameter estimation, but finding the observable and the resulting inversion estimator that saturates this bound remains an open issue for general multi-outcome measurements. Here we consider multi-outcome homodyne detection in a coherent-light Mach-Zehnder interferometer and construct a family of inversion estimators that almost saturate the Cramér-Rao bound over the whole range of phase interval. This provides a clue on constructing optimal inversion estimators for phase estimation and other parameter estimation in any multi-outcome measurement.

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J. Z. Wang, Z. Q. Yang, A. X. Chen, W. Yang, G. R. Jin. 2019-04-01. Multi-outcome homodyne detection in a coherent-state light interferometer. https://doi.org/10.1364/oe.27.010343

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