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Channel correction via quantum erasure

Francesco Buscemi
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Abstract

By exploiting a generalization of recent results on environment-assisted channel correction, we show that, whenever a quantum system undergoes a channel realized as an interaction with a probe, the more efficiently the information about the input state can be erased from the probe, the higher is the corresponding entanglement fidelity of the corrected channel, and vice-versa. The present analysis applies also to channels for which perfect quantum erasure is impossible, thus extending the original quantum eraser arrangement, and naturally embodies a general information-disturbance tradeoff.

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Francesco Buscemi. 2007-09-10. Channel correction via quantum erasure. https://doi.org/10.1103/physrevlett.99.180501

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