Sub-shot-noise shadow sensing with quantum correlations

Toninelli, E., Edgar, M. P., Moreau, P.-A. , Gibson, G. M., Hammond, G. D. and Padgett, M. (2017) Sub-shot-noise shadow sensing with quantum correlations. Optics Express, 25(18), pp. 21826-21840. (doi:10.1364/OE.25.021826)

[img]
Preview
Text
146415.pdf - Published Version
Available under License Creative Commons Attribution.

4MB

Abstract

The quantised nature of the electromagnetic field sets the classical limit to the sensitivity of position measurements. However, techniques based on the properties of quantum states can be exploited to accurately measure the relative displacement of a physical object beyond this classical limit. In this work, we use a simple scheme based on the split-detection of quantum correlations to measure the position of a shadow at the single-photon light level, with a precision that exceeds the shot-noise limit. This result is obtained by analysing the correlated signals of bi-photon pairs, created in parametric downconversion and detected by an electron multiplying CCD (EMCCD) camera employed as a split-detector. By comparing the measured statistics of spatially anticorrelated and uncorrelated photons we were able to observe a significant noise reduction corresponding to an improvement in position sensitivity of up to 17% (0.8dB). Our straightforward approach to sub-shot-noise position measurement is compatible with conventional shadow-sensing techniques based on the split-detection of light-fields, and yields an improvement that scales favourably with the detector’s quantum efficiency.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Gibson, Dr Graham and Hammond, Professor Giles and Padgett, Professor Miles and Edgar, Dr Matthew and Moreau, Dr Paul-Antoine and Toninelli, Mr Ermes
Authors: Toninelli, E., Edgar, M. P., Moreau, P.-A., Gibson, G. M., Hammond, G. D., and Padgett, M.
College/School:College of Science and Engineering > School of Physics and Astronomy
Journal Name:Optics Express
Publisher:Optical Society of America
ISSN:1094-4087
ISSN (Online):1094-4087
Published Online:29 August 2017
Copyright Holders:Copyright © 2017 The Authors
First Published:First published in Optics Express 25(18):21826-21840
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record