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arXiv · 0901.0873

Pure single photon generation by type-I PDC with backward-wave amplification

A. Christ·A. Eckstein·P. J. Mosley·C. Silberhorn
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Abstract

We explore a promising method of generating pure heralded single photons. Our approach is based on parametric downconversion in a periodically-poled waveguide. However, unlike conventional downconversion sources, the photon pairs are counter-propagating: one travels with the pump beam in the forward direction while the other is backpropagating towards the laser source. Our calculations reveal that these downconverted two-photon states carry minimal spectral correlations within each photon-pair. This approach offers the possibility to employ a new range of downconversion processes and materials like PPLN (previously considered unsuitable due to their unfavorable phasematching properties) to herald pure single photons over a broad frequency range.

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A. Christ, A. Eckstein, P. J. Mosley, C. Silberhorn. 2009-02-09. Pure single photon generation by type-I PDC with backward-wave amplification. https://doi.org/10.1364/oe.17.003441

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