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arXiv · 1402.2944

A low-noise frequency down-conversion to the telecommunication band for a quantum communication based on NV centers in diamond

Rikizo Ikuta·Toshiki Kobayashi·Shuto Yasui·Shigehito Miki·Taro Yamashita·Hirotaka Terai·Mikio Fujiwara·Takashi Yamamoto·Masato Koashi·Masahide Sasaki·Zhen Wang·Nobuyuki Imoto
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Abstract

We demonstrate a low-noise frequency down-conversion of photons at 637 nm to the telecommunication band at 1587 nm by the difference frequency generation in a periodically-poled lithium niobate. An internal conversion efficiency of the converter is estimated to be 0.44 at the maximum which is achieved by a pump power of 430 mW, whereas a rate of internal background photons caused by the strong cw pump laser is estimated to be 9 kHz/mW within a bandwidth of about 1 nm. By using the experimental values related to the intrinsic property of the converter, and using the intensity correlation and the average photon number of a 637-nm input light pulse, we derive the intensity correlation of a converted telecom light pulse. Then we discuss feasibility of a single-photon frequency conversion to the telecommunication band for a long-distance quantum communication based on NV centers in diamond.

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Rikizo Ikuta, Toshiki Kobayashi, Shuto Yasui, Shigehito Miki, Taro Yamashita, Hirotaka Terai, Mikio Fujiwara, Takashi Yamamoto, Masato Koashi, Masahide Sasaki, Zhen Wang, Nobuyuki Imoto. 2014-02-12. A low-noise frequency down-conversion to the telecommunication band for a quantum communication based on NV centers in diamond. https://doi.org/10.1364/oe.22.011205

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