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arXiv · 1604.04319

Optical phase estimation via coherent state and displaced photon counting

Shuro Izumi·Masahiro Takeoka·Kentaro Wakui·Mikio Fujiwara·Kazuhiro Ema·Masahide Sasaki
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Abstract

We consider the phase sensing via weak optical coherent state at quantum limit precision. A new detection scheme for the phase estimation is proposed which is inspired by the suboptimal quantum measurement in coherent optical communication. We theoretically analyze a performance of our detection scheme, which we call the displaced-photon counting, for phase sensing in terms of the Fisher information and show that the displaced-photon counting outperforms the static homodyne and heterodyne detections in wide range of the target phase. The proof-of-principle experiment is performed with linear optics and a superconducting nanowire single photon detector. The result shows that our scheme overcomes the limit of the ideal homodyne measurement even under practical imperfections.

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Shuro Izumi, Masahiro Takeoka, Kentaro Wakui, Mikio Fujiwara, Kazuhiro Ema, Masahide Sasaki. 2016-06-21. Optical phase estimation via coherent state and displaced photon counting. https://doi.org/10.1103/physreva.94.033842

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