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Non-linear photonic crystals as a source of entangled photons

Michiel J. A. de Dood·William T. M. Irvine·Dirk Bouwmeester
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Abstract

Non-linear photonic crystals can be used to provide phase-matching for frequency conversion in optically isotropic materials. The phase-matching mechanism proposed here is a combination of form birefringence and phase velocity dispersion in a periodic structure. Since the phase-matching relies on the geometry of the photonic crystal, it becomes possible to use highly non-linear materials. This is illustrated considering a one-dimensional periodic Al$_{0.4}$Ga$_{0.6}$As / air structure for the generation of 1.5 $μ$m light. We show that phase-matching conditions used in schemes to create entangled photon pairs can be achieved in photonic crystals.

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Michiel J. A. de Dood, William T. M. Irvine, Dirk Bouwmeester. 2004-09-25. Non-linear photonic crystals as a source of entangled photons. https://doi.org/10.1103/physrevlett.93.040504

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