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arXiv · 1304.0304

Non-classical two-photon interference between independent telecom light pulses converted by difference-frequency generation

Rikizo Ikuta·Toshiki Kobayashi·Hiroshi Kato·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 demonstrated the Hong-Ou-Mandel (HOM) interference between two photons after visible-to-telecommunication wavelength conversion. In the experiment, we prepared a heralded single photon by using spontaneous parametric down-conversion and the other photon from a weak laser source at 780 nm. We converted the wavelength of both photons to the telecommunication wavelength of 1522 nm by using difference-frequency generation in a periodically-poled lithium niobate, and then observed the HOM interference between the photons. The observed visibility is $0.76\pm 0.12$ which clearly shows the non-classical interference of the two photons. The high-visibility interference is an important step for fiber-based quantum communications of photons generated from visible photon emitters.

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Rikizo Ikuta, Toshiki Kobayashi, Hiroshi Kato, Shigehito Miki, Taro Yamashita, Hirotaka Terai, Mikio Fujiwara, Takashi Yamamoto, Masato Koashi, Masahide Sasaki, Zhen Wang, Nobuyuki Imoto. 2013-04-01. Non-classical two-photon interference between independent telecom light pulses converted by difference-frequency generation. https://doi.org/10.1103/physreva.88.042317

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