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arXiv · 1012.5584

Efficient decoherence-free entanglement distribution over lossy quantum channels

Rikizo Ikuta·Yohei Ono·Toshiyuki Tashima·Takashi Yamamoto·Masato Koashi·Nobuyuki Imoto
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Abstract

We propose and demonstrate a scheme for boosting up the efficiency of entanglement distribution based on a decoherence-free subspace (DFS) over lossy quantum channels. By using backward propagation of a coherent light, our scheme achieves an entanglement-sharing rate that is proportional to the transmittance T of the quantum channel in spite of encoding qubits in multipartite systems for the DFS. We experimentally show that highly entangled states, which can violate the Clauser-Horne-Shimony-Holt inequality, are distributed at a rate proportional to T.

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Rikizo Ikuta, Yohei Ono, Toshiyuki Tashima, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto. 2011-06-09. Efficient decoherence-free entanglement distribution over lossy quantum channels. https://doi.org/10.1103/physrevlett.106.110503

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