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Experimental reversion of the optimal quantum cloning and flipping processes

Fabio Sciarrino·Veronica Secondi·Francesco De Martini
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Abstract

The quantum cloner machine maps an unknown arbitrary input qubit into two optimal clones and one optimal flipped qubit. By combining linear and non-linear optical methods we experimentally implement a scheme that, after the cloning transformation, restores the original input qubit in one of the output channels, by using local measurements, classical communication and feedforward. This significant teleportation-like method demonstrates how the information is preserved during the cloning process. The realization of the reversion process is expected to find useful applications in the field of modern multi-partite quantum cryptography.

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Fabio Sciarrino, Veronica Secondi, Francesco De Martini. 2005-04-28. Experimental reversion of the optimal quantum cloning and flipping processes. https://doi.org/10.1103/physreva.73.040303

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