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Optica Advanced Photonics Congress

Generating Spatially Entangled Qubits using Quantum Nonlinear Holography

Ofir Yesharim, Shaul Pearl, Joshua Foley-Comer, Irit Juwiler, Ady Arie

Published Jan 1, 2022• 0 citations
Publisher

Abstract

We experimentally shape the quantum correlations of spatially entangled photon pairs in a two-dimensionally patterned KTiOPO4 crystal using nonlinear holography. Our method enables multi-dimensional engineering of quantum states directly using patterned nonlinear photonic crystals.
DOI
10.1364/np.2022.nptu4g.3

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We present theoretical and experimental advances on photon-pair generation through spontaneous parametric down-conversion (SPDC) in nonlinear nanostructures and metasurfaces, underpinning quantum entanglement engineering at sub-wavelength scale for photon shaping with tailored polarization and spatial correlations. We derive explicit theoretical expressions for the measurable photon counts and quantum correlations, incorporating material dispersion and absorption characteristics [Phys. Rev. Lett. 117, 123901 (2016)], and demonstrate experimentally the generation of quantum heralded photon pairs from a single AlGaAs nanodisk [Optica 6, 1416 (2019)]. We further reveal the opportunities to enhance the generation rate through high-Q resonances including bound states in the continuum [doi:10.1117/12.2539888 (2019)]. We also outline the applications of metasurfaces for the manipulation and measurement of multi-photon quantum states for free-space quantum imaging and communications.