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Faithful qubit distribution assisted by one additional qubit against collective noise

T. Yamamoto·J. Shimamura·S. K. Ozdemir·M. Koashi·N. Imoto
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Abstract

We propose a distribution scheme of polarization states of a single photon over collective-noise channel. By adding one extra photon with a fixed polarization, we can protect the state against collective noise via a parity-check measurement and post-selection. While the scheme succeeds only probabilistically, it is simpler and more flexible than the schemes utilizing decoherence-free subspace. An application to BB84 protocol through collective noise channel, which is robust to the Trojan horse attack, is also given.

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T. Yamamoto, J. Shimamura, S. K. Ozdemir, M. Koashi, N. Imoto. 2005-07-27. Faithful qubit distribution assisted by one additional qubit against collective noise. https://doi.org/10.1103/physrevlett.95.040503

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