English

Useful Multiparticle Entanglement and Sub-Shot-Noise Sensitivity in Experimental Phase Estimation

Quantum Physics 2015-05-30 v1

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.

Keywords

Cite

@article{arxiv.1108.6002,
  title  = {Useful Multiparticle Entanglement and Sub-Shot-Noise Sensitivity in Experimental Phase Estimation},
  author = {Roland Krischek and Christian Schwemmer and Witlef Wieczorek and Harald Weinfurter and Philipp Hyllus and Luca Pezzé and Augusto Smerzi},
  journal= {arXiv preprint arXiv:1108.6002},
  year   = {2015}
}

Comments

4 pages, 4 figures

R2 v1 2026-06-21T18:57:19.169Z