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arXiv · 2111.10981

Generation of spectrally factorable photon pairs via multi-order quasi-phase-matched spontaneous parametric downconversion

Fumihiro Kaneda·Jo Oikawa·Masahiro Yabuno·Fumihiro China·Shigehito Miki·Hirotaka Terai·Yasuyoshi Mitsumori·Keiichi Edamatsu
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Abstract

For advanced quantum information technology, sources of photon pairs in quantum mechanically factorable states are of great importance for realizing high-fidelity photon-photon quantum gate operations. Here we experimentally demonstrate a technique to produce spectrally factorable photon pairs utilizing multi-order quasi-phase-matching (QPM) conditions in spontaneous parametric downconversion (SPDC). In our scheme, a spatial nonlinearity profile of a nonlinear optical crystal is shaped with current standard poling techniques, and the associated phase-matching function can be approximated to a Gaussian form. By the measurement of a phase-matching function and the second-order autocorrelation function, we demonstrate that telecom-band photon pairs produced by our custom-poled crystal are highly factorable with > 95% single-photon purity.

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Fumihiro Kaneda, Jo Oikawa, Masahiro Yabuno, Fumihiro China, Shigehito Miki, Hirotaka Terai, Yasuyoshi Mitsumori, Keiichi Edamatsu. 2021-11-22. Generation of spectrally factorable photon pairs via multi-order quasi-phase-matched spontaneous parametric downconversion. https://arxiv.org/abs/2111.10981

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