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Highly asymmetric quantum cloning in arbitrary dimension

Jaromir Fiurasek·Radim Filip·Nicolas J. Cerf
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Abstract

We investigate the universal asymmetric cloning of states in a Hilbert space of arbitrary dimension. We derive the class of optimal and fully asymmetric 1->3 cloners, which produce three copies, each having a different fidelity. A simple parametric expression for the maximum achievable cloning fidelity triplets is then provided. As a side-product, we also prove the optimality of the 1->2 asymmetric cloning machines that have been proposed in the literature.

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Jaromir Fiurasek, Radim Filip, Nicolas J. Cerf. 2005-05-27. Highly asymmetric quantum cloning in arbitrary dimension. https://arxiv.org/abs/quant-ph/0505212

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