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Quantum 2.0 Conference and Exhibition

Joint spectral characterization of SOI integrated directional coupler using Hong-Ou-Mandel interference

Yoel Olivier, Dan Cohen, Leonid Vidro, H. S. Eisenberg, Matan Slook, Mirit Hen, Avi Zadok

Published Jan 1, 2024• 0 citations
Publisher

Abstract

We characterize the spectral response of a silicon chip integrated non-perfect directional coupler by measuring the biphoton joint spectrum at the Hong-Ou-Mandel dip and show the resulting spectral coupling dependency.
DOI
10.1364/quantum.2024.qw3a.42

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Near-infrared Hong-Ou-Mandel quantum interference is observed in silicon nanophotonic directional couplers with raw visibilities on-chip at 90.5%. Spectrally-bright 1557-nm two-photon states are generated in a periodically-poled KTiOPO₄ waveguide chip, serving as the entangled photon source and pumped with a self-injection locked laser, for the photon statistical measurements. Efficient four-port coupling in the communications C-band and in the high-index-contrast silicon photonics platform is demonstrated, with matching theoretical predictions of the quantum interference visibility. Constituents for the residual quantum visibility imperfection are examined, supported with theoretical analysis of the sequentially-triggered multipair biphoton, towards scalable high-bitrate quantum information processing and communications. The on-chip HOM interference is useful towards scalable high-bitrate quantum information processing and communications.
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