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arXiv · 1501.05686

Modified E91 protocol demonstration with hybrid entanglement photon source

Mikio Fujiwara·Ken-ichiro Yoshino·Yoshihiro Nambu·Taro Yamashita·Shigehito Miki·Hirotaka Terai·Zhen Wang·Morio Toyoshima·Akihisa Tomita·Masahide Sasaki
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Abstract

We report on an experimental demonstration of the modified Ekert 91 protocol of quantum key distribution using a hybrid entanglement source with two different degrees of freedoms, a 1550 nm time-bin qubit and 810 nm polarization qubit. The violation of the Clauser-Horne-Shimony-Holt inequality could be demonstrated for the entanglement between the polarization qubit in free space and the time-bin qubit through 20 km fiber transmission. The secure key rate in our system is estimated 70-150 bps.

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Mikio Fujiwara, Ken-ichiro Yoshino, Yoshihiro Nambu, Taro Yamashita, Shigehito Miki, Hirotaka Terai, Zhen Wang, Morio Toyoshima, Akihisa Tomita, Masahide Sasaki. 2015-01-23. Modified E91 protocol demonstration with hybrid entanglement photon source. https://doi.org/10.1364/oe.22.013616

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