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arXiv · 1003.0831

Anomalous resilient to decoherence macroscopic quantum superpositions generated by universally covariant optimal quantum cloning

N. Spagnolo·F. Sciarrino·F. De Martini
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Abstract

We show that the quantum states generated by universal optimal quantum cloning of a single photon represent an universal set of quantum superpositions resilient to decoherence. We adopt Bures distance as a tool to investigate the persistence ofquantum coherence of these quantum states. According to this analysis, the process of universal cloning realizes a class of quantum superpositions that exhibits a covariance property in lossy configuration over the complete set of polarization states in the Bloch sphere.

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N. Spagnolo, F. Sciarrino, F. De Martini. 2010-03-03. Anomalous resilient to decoherence macroscopic quantum superpositions generated by universally covariant optimal quantum cloning. https://doi.org/10.1103/physreva.82.032325

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