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arXiv · 1906.12294

Distributed Quantum Metrology with a Single Squeezed-Vacuum Source

Dario Gatto·Paolo Facchi·Frank Narducci·Vincenzo Tamma
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Abstract

We propose an interferometric scheme for the estimation of a linear combination with non-negative weights of an arbitrary number $M>1$ of unknown phase delays, distributed across an $M$-channel linear optical network, with Heisenberg-limited sensitivity. This is achieved without the need of any sources of photon-number or entangled states, photon-number resolving detectors or auxiliary interferometric channels. Indeed, the proposed protocol remarkably relys upon a single squeezed state source, an antisqueezing operation at the interferometer output, and on-off photodetectors.

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Dario Gatto, Paolo Facchi, Frank Narducci, Vincenzo Tamma. 2019-06-28. Distributed Quantum Metrology with a Single Squeezed-Vacuum Source. https://doi.org/10.1103/physrevresearch.1.032024

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