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arXiv · 0906.5494

Optimal cloning with respect to the relative error

Alexey E. Rastegin
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Abstract

The relative error of cloning of quantum states with arbitrary prior probabilities is considered. It is assumed that the ancilla may contain some a priori information about the input state to be cloned. The lower bound on the relative error for general cloning scenario is derived. Both the case of two-state set and case of multi-state set are analyzed in details. The treated figure of merit is compared with other optimality criteria. The quantum circuit for optimal cloning of a pair of pure states is constructed.

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Alexey E. Rastegin. 2010-06-17. Optimal cloning with respect to the relative error. https://arxiv.org/abs/0906.5494

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