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Superbroadcasting of mixed states

Giacomo Mauro D'Ariano·Chiara Macchiavello·Paolo Perinotti
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Abstract

We derive the optimal universal broadcasting for mixed states of qubits. We show that the nobroadcasting theorem cannot be generalized to more than a single input copy. Moreover, for four or more input copies it is even possible to purify the input states while broadcasting. We name such purifying broadcasting superbroadcasting.

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Giacomo Mauro D'Ariano, Chiara Macchiavello, Paolo Perinotti. 2005-06-29. Superbroadcasting of mixed states. https://doi.org/10.1103/physrevlett.95.060503

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