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Quantum 2.0 Conference and Exhibition

Hong-Ou-Mandel interference of two photons of vastly different color

Felix Mann, Helen M. Chrzanowski, Felipe Lucas Gewers, Marlon Plack, Sven Ramelow

Published Jan 1, 2024• 1 citation
Publisher

Abstract

Hong-Ou-Mandel interference is a quantum phenomenon that underlies quantum information processing with single photons. Using a quantum frequency converter as an active beam splitter we demonstrate Hong-Ou-Mandel interference of two photons of vastly different colors.
DOI
10.1364/quantum.2024.qm2b.6

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The Hong-Ou-Mandel (HOM) interference is one of the most fundamental quantum-mechanical effects that reveal a nonclassical behavior of single photons. Two identical photons that are incident on the input ports of an unbiased beam splitter always exit the beam splitter together from the same output port, an effect referred to as photon bunching. In this Letter, we utilize a single electro-optic phase modulator as a probabilistic frequency beam splitter, which we exploit to observe HOM interference between two photons that are in different spectral modes, yet are identical in other characteristics. Our approach enables linear optical quantum information processing protocols using the frequency degree of freedom in photons such as quantum computing techniques with linear optics.