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Separating the classical and quantum information via quantum cloning

M. Ricci·F. Sciarrino·N. J. Cerf·R. Filip·J. Fiurasek·F. De Martini
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Abstract

An application of quantum cloning to optimally interface a quantum system with a classical observer is presented, in particular we describe a procedure to perform a minimal disturbance measurement on a single qubit by adopting a 1->2 cloning machine followed by a generalized measurement on a single clone and the anti-clone or on the two clones. Such scheme has been applied to enhance the transmission fidelity over a lossy quantum channel.

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M. Ricci, F. Sciarrino, N. J. Cerf, R. Filip, J. Fiurasek, F. De Martini. 2005-08-06. Separating the classical and quantum information via quantum cloning. https://doi.org/10.1103/physrevlett.95.090504

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