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arXiv · 1310.0443

Quantum-enhanced Phase Estimation with an Amplified Bell State

Jaspreet Sahota·Daniel F. V. James
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Abstract

We propose a phase estimation protocol for optical interferometry that employs a probe state (containing on average n photons) obtained by squeezing each mode, separately, of a single photon path entangled Bell state. This scheme involves a Mach-Zehnder type interferometer for which each mode is squeezed after the first beam splitter. Information about the differential phase is extracted using a parity detection and the resulting measurement signal is super-resolving and supersensitive, with a minimum phase uncertainty 2/(n+1). This probe state can be generated with current technologies where n is in the order of many thousands of photons.

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Jaspreet Sahota, Daniel F. V. James. 2014-01-03. Quantum-enhanced Phase Estimation with an Amplified Bell State. https://doi.org/10.1103/physreva.88.063820

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