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arXiv · 2603.28519

Photon-triplets for quantum optics generated by a phase-matched third-order difference-frequency mixing in a KTiOPO4 bulk crystal pumped at 532 nm

Abstract

We report implementation and modelling of an efficient photon-triplets generation experiment based on a difference-frequency-mixing of two picosecond beams at 532 nm and 1491 nm in a type II phase-matched KTP crystal. The photon-triplets flux was measured as a function of the energy of the two incident beams using a coincidence protocol. A maximal flux of 11.6 photon-triplets per second was achieved. These experimental data were satisfactorily described by a semiclassical model based on the quantum fluctuations of vacuum and the classical equations of nonlinear optics.

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Gaspar Mougin-Trichon, Veronique Boutou, Corinne Felix, David Jegouso, Benoit Boulanger. 2026-03-30. Photon-triplets for quantum optics generated by a phase-matched third-order difference-frequency mixing in a KTiOPO4 bulk crystal pumped at 532 nm. https://arxiv.org/abs/2603.28519

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