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arXiv · 1607.07314

Experimental demonstration of robust entanglement distribution over reciprocal noisy channels assisted by a counter-propagating classical reference light

Rikizo Ikuta·Shota Nozaki·Takashi Yamamoto·Masato Koashi·Nobuyuki Imoto
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Abstract

We experimentally demonstrate a proposal [Phys. Rev. A 87, 052325 (2013)] of a scheme for robust distribution of polarization entangled photon pairs over collective noisy channels having the reciprocity. Although the scheme employs the robustness of two qubit decoherence-free subspace, by utilizing the forward propagation of one half of the entangled photons and the backward propagation of a classical reference light, it achieves an entanglement-sharing rate proportional to the transmittance of the quantum channel for the signal photon. We experimentally observed the efficient sharing rate while keeping a highly entangled state after the transmission. We also show that the protection method is applicable to transmission of arbitrary polarization state of a single photon.

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Rikizo Ikuta, Shota Nozaki, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto. 2016-07-25. Experimental demonstration of robust entanglement distribution over reciprocal noisy channels assisted by a counter-propagating classical reference light. https://doi.org/10.1038/s41598-017-05008-6

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