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Enhanced Entangled Second Harmonic Generation Beyond the Photon Pairs Regime

T. Dickinson, Ivi Afxenti, Giedre Astrauskaite, Lennart Hirsch, Samuel Nerenberg, O. Jedrkiewicz, D. Faccio, C. Müllenbroich, A. Gatti, M. Clerici, Lucia Caspani

Published Jan 1, 2025• 0 citations

Abstract

We report quantum-enhanced second harmonic generation driven by parametric down-conversion, with efficiencies surpassing those of classical light beyond the photon-pair regime. Experiments confirm a persistent quantum advantage up to ~10 photons per mode, extending nonlinear quantum enhancement toward practical applications.

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