Journal of Modern Optics

A pump enhanced source of telecom-band correlated photon pairs

Peter James Thomas, Malcolm H. Dunn, David J. M. Stothard, D. Walsh, Christopher J. Chunnilall

Published Mar 9, 2011• 2 citations

Abstract

Correlated photon pairs generated through spontaneous parametric downconversion have become a key resource for research into enhanced optical measurement and quantum optical information processing. A pump-enhanced χ(2) source of correlated photons in the telecom band is presented. An investigation of the pair photon coincidence detection rate measured from the source, together with the evaluation of system losses, indicated a single spatial fibre-optic mode pair production rate of 6.12 × 104 s−1 mW−1 pump power, an order of magnitude greater than was measured without enhancement. A Hong-Ou-Mandel interference experiment confirmed that the enhancement did not have any adverse effect on the spatial and frequency indistinguishability of the emitted pairs. The source comprises a symmetric and linear enhancement cavity for the pump, making it particularly suitable for generating polarisation entangled photon pairs without the need for compensating crystals 1 Thomas, PJ, Chunnilall, CJ, Stothard, DJM, Walsh, DA and Dunn, MH. 2010. Opt. Express, 18: 26600–26612. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar].

DOI: 10.1080/09500340.2011.561421

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