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arXiv · 1703.08114

Mach-Zehnder interferometer using frequency-domain beamsplitter

Toshiki Kobayashi·Daisuke Yamazaki·Kenichiro Matsuki·Rikizo Ikuta·Shigehito Miki·Taro Yamashita·Hirotaka Terai·Takashi Yamamoto·Masato Koashi·Nobuyuki Imoto
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Abstract

We demonstrated the first-order interference between coherent light at 1580 nm and 795 nm by using frequency-domain Mach-Zehnder interferometer (MZI). The MZI is implemented by two frequency-domain BSs based on a second-order nonlinear optical effect in a periodically-poled lithium niobate waveguide with a strong pump light. We achieved the visibility of over 0.99 at 50% conversion efficiencies of the BSs. Toward photonic quantum information processing, sufficiently small background photon rate is necessary. From the measurement results with a superconducting single photon detector, we discuss the feasibility of the frequency-domain MZI in a quantum regime. Our estimation shows that single photon interference with the visibility above 0.9 is feasible with practical settings.

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Toshiki Kobayashi, Daisuke Yamazaki, Kenichiro Matsuki, Rikizo Ikuta, Shigehito Miki, Taro Yamashita, Hirotaka Terai, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto. 2017-03-23. Mach-Zehnder interferometer using frequency-domain beamsplitter. https://doi.org/10.1364/oe.25.012052

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