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arXiv · 1112.2019

Four-Photon Quantum Interferometry at a Telecom Wavelength

Masahiro Yabuno·Ryosuke Shimizu·Yasuyoshi Mitsumori·Hideo Kosaka·Keiichi Edamatsu
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Abstract

We report the experimental demonstration of four-photon quantum interference using telecom-wavelength photons. Realization of multi-photon quantum interference is essential to linear optics quantum information processing and measurement-based quantum computing. We have developed a source that efficiently emits photon pairs in a pure spectrotemporal mode at a telecom wavelength region, and have demonstrated the quantum interference exhibiting the reduced fringe intervals that correspond to the reduced de Broglie wavelength of up to the four photon `NOON' state. Our result should open a path to practical quantum information processing using telecom-wavelength photons.

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Masahiro Yabuno, Ryosuke Shimizu, Yasuyoshi Mitsumori, Hideo Kosaka, Keiichi Edamatsu. 2011-12-09. Four-Photon Quantum Interferometry at a Telecom Wavelength. https://doi.org/10.1103/physreva.86.010302

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