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Experimental phase-covariant cloning of polarization states of single photons

A. Cernoch·L. Bartuskova·J. Soubusta·M. Jezek·J. Fiurasek·M. Dusek
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Abstract

The experimental realization of optimal symmetric phase-covariant 1->2 cloning of qubit states is presented. The qubits are represented by polarization states of photons generated by spontaneous parametric down-conversion. The experiment is based on the interference of two photons on a custom-made beam splitter with different splitting ratios for vertical and horizontal polarization components. From the measured data we have estimated the implemented cloning transformation using the maximum-likelihood method. The result shows that the realized transformation is very close to the ideal one and the map fidelity reaches 94%.

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A. Cernoch, L. Bartuskova, J. Soubusta, M. Jezek, J. Fiurasek, M. Dusek. 2006-07-21. Experimental phase-covariant cloning of polarization states of single photons. https://doi.org/10.1103/physreva.74.042327

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