Sensitivity Bounds for Multiparameter Quantum Metrology.

Phys Rev Lett

QSTAR, CNR-INO and LENS, Largo Enrico Fermi 2, I-50125 Firenze, Italy.

Published: September 2018

We identify precision limits for the simultaneous estimation of multiple parameters in multimode interferometers. Quantum strategies to enhance the multiparameter sensitivity are based on entanglement among particles, modes, or combining both. The maximum attainable sensitivity of particle-separable states defines the multiparameter shot-noise limit, which can be surpassed without mode entanglement. Further enhancements up to the multiparameter Heisenberg limit are possible by adding mode entanglement. Optimal strategies that saturate the precision bounds are provided.

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http://dx.doi.org/10.1103/PhysRevLett.121.130503DOI Listing

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