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Quantum 2.0 Conference and Exhibition

Engineering Spectral Purity of Telecom Wavelength Photons Generated via SPDC for Multi-partite Quantum Communication

Johanna Conrad, Rodrigo Gómez, Markus Leipe, Meritxell Cabrejo Ponce, Fabian Steinlechner

Published Jan 1, 2024• 0 citations
Publisher

Abstract

We report on engineering spectrally pure photon pairs via SPDC and provide a comprehensive characterization of periodically and aperiodically poled KTP crystals as well as Hong-Ou-Mandel experiments between photons produced in distinct SPDC crystals.
DOI
10.1364/quantum.2024.qth3a.2

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The generation of high purity single photons and entangled photon pairs is a crucial first step in many quantum optics experiments, including those that require quantum teleportation [1], entanglement swapping [2], and the generation of multi-photon entanglement [3]. The most widely used and established approach for creating photon pairs is spontaneous parametric down conversion (SPDC) - where pump photons undergo a non-linear optical process to create a down-converted photon pair [4]. Traditionally, the generation of high-purity heralded single photons required severe spectral filtering, introducing additional loss. However, through careful engineering of spectral correlations of the down-converted photon pairs one can circumvent the need for filtering and avoid the accompanying reduction in heralding efficiency.
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