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arXiv · 1810.02052

Direct generation of frequency-bin entangled photons via two-period quasi-phase-matched parametric downconversion

Fumihiro Kaneda·Hirofumi Suzuki·Ryosuke Shimizu·Keiichi Edamatsu
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Abstract

We report a simple scheme for direct generation of frequency-bin entangled photon pairs via spontaneous parametric downconversion. Our fabricated nonlinear optical crystal with two different poling periods can simultaneously satisfy two different, spectrally symmetric nondegenerate quasi-phase-matching conditions, enabling the direct generation of entanglement in two discrete frequency-bin modes. Our produced photon pairs exhibited Hong-Ou-Mandel interference with high-visibility beating oscillations, a signature of two-mode frequency-bin entanglement. Moreover, we demonstrate deterministic entanglement-mode conversion from frequency-bin to polarization modes, with which our source can be more versatile for various quantum applications. Our scheme can be extended to direct generation of high-dimensional frequency-bin entanglement, and thus will be a key technology for frequency-multiplexed optical quantum information processing.

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Fumihiro Kaneda, Hirofumi Suzuki, Ryosuke Shimizu, Keiichi Edamatsu. 2018-10-04. Direct generation of frequency-bin entangled photons via two-period quasi-phase-matched parametric downconversion. https://doi.org/10.1364/oe.27.001416

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