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arXiv · 0806.2896

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

Takashi Yamamoto·Kodai Hayashi·Sahin Kaya Ozdemir·Masato Koashi·Nobuyuki Imoto
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Abstract

Efficient and faithful implementation of quantum information tasks, e.g., quantum computing, quantum communication and quantum metrology, requires robust and state-independent decoherence-suppressing measures to protect quantum information carriers. Here we present an experimental demonstration of a robust distribution scheme in which one photon of an entangled photon pair is successfully encoded into and decoded from a decoherence-free subspace (DFS) by a state-independent scheme. We achieved a high-fidelity distribution of the entangled state over fibre communication channel, and also demonstrated that the scheme is robust against fragility of the reference frame. The scheme, thanks to its state-independence, is also applicable to multipartite case where the photon to be distributed is entangled with many other photons. Such a universal scheme opens the possibility of robust distribution of quantum information among quantum communication and computing networks.

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Takashi Yamamoto, Kodai Hayashi, Sahin Kaya Ozdemir, Masato Koashi, Nobuyuki Imoto. 2008-06-18. Robust photonic entanglement distribution via state-independent encoding onto decoherence-free subspace. https://doi.org/10.1038/nphoton.2008.130

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