Useful multiparticle entanglement and sub-shot-noise sensitivity in experimental phase estimation
Authors: Krischek R., Schwemmer C., Wieczorek W., Weinfurter H., Hyllus P., Pezze L., Smerzi A.
Autors Affiliation: Fakultat fur Physik, Ludwig-Maximilians Universitat Munchen, D-80799 Munchen, Germany; Max-Planck Institut fur Quantenoptik, Hans-Kopfermann Strasse 1, D-85748 Garching, Germany; INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, I-38123 Povo, Italy; Laboratoire Charles Fabry UMR 8501, Institut d’Optique, CNRS, Université Paris Sud 11, 2 Avenue Fresnel, 91127 Palaiseau cedex, France
Abstract: We experimentally demonstrate a general criterion to identify entangled states useful for the estimation of an unknown phase shift with a sensitivity higher than the shot-noise limit. We show how to exploit this entanglement on the examples of a maximum likelihood as well as of a Bayesian phase estimation protocol. Using an entangled four-photon state we achieve a phase sensitivity clearly beyond the shot-noise limit. Our detailed comparison of methods and quantum states for entanglement enhanced metrology reveals the connection between multiparticle entanglement and sub-shot-noise uncertainty, both in a frequentist and in a Bayesian phase estimation setting.
Journal/Review: PHYSICAL REVIEW LETTERS
Volume: 107 (8) Pages from: 080504 to: 080504
More Information: We thank N. Kiesel, W. Laskowski, and O. Guhne for stimulating discussions. R.K., C.S., W.W., and H.W. acknowledge the support of the DFG-Cluster of Excellence MAP, the EU projects QAP and Q-Essence, and the DAAD/MNISW exchange program. W.W. and C. S. thank QCCC of the Elite Network of Bavaria and P.H. thanks the ERC Starting Grant GEDENTQOPT.DOI: 10.1103/PhysRevLett.107.080504Citations: 68data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-08-02References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here