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arXiv · 1706.05492

Multiparameter estimation with single photons

Chenglong You·Sushovit Adhikari·Yuxi Chi·Margarite L. LaBorde·Corey T. Matyas·Chenyu Zhang·Zuen Su·Tim Byrnes·Chaoyang Lu·Jonathan P. Dowling·Jonathan P. Olson
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Abstract

It was suggested in Ref. [Phys. Rev. Lett. 114, 170802] that optical networks with relatively inexpensive overhead---single photon Fock states, passive optical elements, and single photon detection---can show significant improvements over classical strategies for single-parameter estimation, when the number of modes in the network is small (n < 7). A similar case was made in Ref. [Phys. Rev. Lett. 111, 070403] for multi-parameter estimation, where measurement is instead made using photon-number resolving detectors. In this paper, we analytically compute the quantum Cramér-Rao bound to show these networks can have a constant-factor quantum advantage in multi-parameter estimation for even large number of modes. Additionally, we provide a simplified measurement scheme using only single-photon (on-off) detectors that is capable of approximately obtaining this sensitivity for a small number of modes.

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Chenglong You, Sushovit Adhikari, Yuxi Chi, Margarite L. LaBorde, Corey T. Matyas, Chenyu Zhang, Zuen Su, Tim Byrnes, Chaoyang Lu, Jonathan P. Dowling, Jonathan P. Olson. 2017-06-17. Multiparameter estimation with single photons. https://doi.org/10.1088/2040-8986%2Faa9133

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