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OPTIMAL CLONING AND NO SIGNALING

Sibasish Ghosh A, Guruprasad Kar, Anirban Roy Physics

Published Jan 1, 1999• 25 citations
OpenAlex

Abstract

It is shown that no signaling constraint generates the whole class of 1 → 2 optimal quantum cloning machines of single qubits

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In this project, quantum cloning machines are analyzed that take in N quantum systems in the same unknown pure state and output M quantum systems with M > N, such that the output best resembles the ideal, but impossible output of an M-fold tensor product of the pure input state. The proof of Keyl and Werner is reviewed in which a unique optimal solution is constructed, both in the case where the quality of the cloning is determined by the entire output, and in the case where the quality is determined by measurements on a single clone. Furthermore, it is shown that previous work on qubit cloning machines is a special case of the presented optimal solution.
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