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arXiv:0806.2896 · Nature Photonics

Robust photonic entanglement distribution by state-independent encoding onto decoherence-free subspace

Takashi Yamamoto, Kodai Hayashi, Şahin Kaya Özdemir, Masato Koashi, Nobuyuki Imoto

Published Jul 11, 2008• 55 citations
arXivHTMLPDF
DOI
10.1038/nphoton.2008.130

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We propose a photonic procedure using cross-Kerr nonlinearities (XKNLs) to encode single logical qubit information onto four-photon decoherence-free states. In quantum information processing, a decoherence-free subspace can secure quantum information against collective decoherence. Therefore, we design a procedure employing nonlinear optical gates, which are composed of XKNLs, quantum bus beams, and photon-number-resolving measurements with linear optical devices, to conserve quantum information by encoding quantum information onto four-photon decoherence-free states (single logical qubit information). Based on our analysis in quantifying the affection (photon loss and dephasing) of the decoherence effect, we demonstrate the experimental condition to acquire the reliable procedure of single logical qubit information having the robustness against the decoherence effect.