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Global-fidelity limits of state-dependent cloning of mixed states

Alexey E. Rastegin
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Abstract

By relevant modifications, the known global-fidelity limits of state-dependent cloning are extended to mixed quantum states. We assume that the ancilla contains some a priori information about the input state. As it is shown, the obtained results contribute to the stronger no-cloning theorem. An attainability of presented limits is discussed.

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Alexey E. Rastegin. 2003-10-17. Global-fidelity limits of state-dependent cloning of mixed states. https://doi.org/10.1103/physreva.68.032303

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