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arXiv · 0906.0182

Optimal mirror phase-covariant cloning

Karol Bartkiewicz·Adam Miranowicz·Şahin Kaya Özdemir
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Abstract

We propose a quantum cloning machine, which clones a qubit into two clones assuming known modulus of expectation value of Pauli Z-matrix. The process is referred to as the mirror phase-covariant cloning, for which the input state is a priori less known than that for the standard phase-covariant cloning. Analytical expressions describing the cloning transformation and fidelity of the clones are found. Extremal equations for the optimal cloning are derived and analytically solved by generalizing a method of Fiurasek [Phys. Rev. A 64, 062310 (2001)]. Quantum circuits implementing the optimal cloning transformation and their physical realization in a quantum-dot system are described.

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Karol Bartkiewicz, Adam Miranowicz, Şahin Kaya Özdemir. 2009-09-10. Optimal mirror phase-covariant cloning. https://doi.org/10.1103/physreva.80.032306

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