Precise Phase Measurements using an Entangled Coherent State

P. A. Knott, J. A. Dunningham

Abstract

Quantum entanglement offers the possibility of making measurements beyond the classical limit, however some issues still need to be overcome before it can be applied in realistic lossy systems. Recent work has used quantum Fisher information (QFI) to show that entangled coherent states (ECSs) may be useful for this purpose as they combine sub-classical phase precision capabilities with robustness (Joo et al., 2011). However, to date no effective scheme for measuring a phase in lossy systems using an ECS has been devised. Here we present a scheme that does just this. We show how one could measure a phase to a precision significantly better than that attainable by both unentangled ‘classical’ states and highly-entangled NOON states over a wide range of different losses. This brings quantum metrology closer to being a realistic and practical technology.

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Paper Citation


in Harvard Style

Knott P. and Dunningham J. (2014). Precise Phase Measurements using an Entangled Coherent State . In Proceedings of 2nd International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS, ISBN 978-989-758-008-6, pages 205-211. DOI: 10.5220/0004734902050211


in Bibtex Style

@conference{photoptics14,
author={P. A. Knott and J. A. Dunningham},
title={Precise Phase Measurements using an Entangled Coherent State},
booktitle={Proceedings of 2nd International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,},
year={2014},
pages={205-211},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004734902050211},
isbn={978-989-758-008-6},
}


in EndNote Style

TY - CONF
JO - Proceedings of 2nd International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,
TI - Precise Phase Measurements using an Entangled Coherent State
SN - 978-989-758-008-6
AU - Knott P.
AU - Dunningham J.
PY - 2014
SP - 205
EP - 211
DO - 10.5220/0004734902050211