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arXiv:quant-ph/0410054 · Quantum Information and Computation

Asymmetric phase covariant d-dimensional cloning

L.-P. Lamoureux, Nicolas J. Cerf

Published Jan 1, 2005• 8 citations
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Abstract

We consider cloning transformations of d-dimensional states of the form $e^{i\phi_0}|0> + e^{i\phi_1}|1> +...+ e^{i\phi_{d-1}}|d-1>$ that are covariant with respect to rotations of the phases $\phi_i$'s. The optimal cloning maps are easily obtained using a well-defined general characterization of state-dependent $1 \rightarrow 2$ cloning transformations in arbitrary dimensions. Our results apply to symmetric as well as asymmetric cloners, so that the balance between the fidelity of the two clones can be analyzed.

DOI
10.26421/qic5.1-3

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