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arXiv · 1207.1585

High-fidelity conversion of photonic quantum information to telecommunication wavelength with superconducting single-photon detectors

Rikizo Ikuta·Hiroshi Kato·Yoshiaki Kusaka·Shigehito Miki·Taro Yamashita·Hirotaka Terai·Mikio Fujiwara·Takashi Yamamoto·Masato Koashi·Masahide Sasaki·Zhen Wang·Nobuyuki Imoto
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Abstract

We experimentally demonstrate a high-fidelity visible-to-telecommunication wavelength conversion of a photon by using a solid-state-based difference frequency generation. In the experiment, one half of a pico-second visible entangled photon pair at 780 nm is converted to a 1522-nm photon, resulting in the entangled photon pair between 780 nm and 1522 nm. Using superconducting single-photon detectors with low dark count rates and small timing jitters, we selectively observed well-defined temporal modes containing the two photons. We achieved a fidelity of $0.93 \pm 0.04$ after the wavelength conversion, indicating that our solid-state-based scheme can be used for faithful frequency down-conversion of visible photons emitted from quantum memories composed of various media.

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Rikizo Ikuta, Hiroshi Kato, Yoshiaki Kusaka, Shigehito Miki, Taro Yamashita, Hirotaka Terai, Mikio Fujiwara, Takashi Yamamoto, Masato Koashi, Masahide Sasaki, Zhen Wang, Nobuyuki Imoto. 2012-07-06. High-fidelity conversion of photonic quantum information to telecommunication wavelength with superconducting single-photon detectors. https://doi.org/10.1103/physreva.87.010301

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