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Frontiers in Optics

Higher-Order Spontaneous Parametric Down-Conversion With Back-Propagating Idler Using Submicron Poled KTP

Mark Bashkansky, I. Vurgaftman, John F. Reintjes

Published Jan 1, 2015• 0 citations
Publisher

Abstract

We demonstrate Spontaneous Parametric Down-Conversion in one-dimensional periodically poled KTP waveguide with counter-propagating signal and idler beams. This is accomplished by using sub-micron poling and higher-order quasi-phase-matching interactions.
DOI
10.1364/fio.2015.fm3d.3

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Entangled photons, which may be generated through the process of spontaneous parametric down-conversion (SPDC) in a crystal with /spl chi//sup (2)/ nonlinearity, have long been in the spotlight for quantum-optics experiments. The generation of entangled photons by quasi-phase matching (QPM) in lithium niobate offers the promise of increased photon-pair production and, with the integration of a waveguide structure, control of the spatial characteristics of the down-converted photons. It turns out that the use of a waveguide structure, in conjunction with periodic poling to achieve quasi-phase matching, offers another critically important feature: the possibility of generating counterpropagating signal and idler photons. We consider the conditions required for generating counterpropagating photon beams and explore some of the unique properties of this source of light using a periodically poled LiNbO/sub 3/ waveguide.
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