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arXiv · 1102.3809

Perturbative quantum error correction

Cédric Bény
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Abstract

We derive simple necessary and sufficient conditions under which a quantum channel obtained from an arbitrary perturbation from the identity can be reversed on a given code to the lowest order in fidelity. We find the usual Knill-Laflamme conditions applied to a certain operator subspace which, for a generic perturbation, is generated by the Lindblad operators. For a weak interaction with an environment, the error space to be corrected is a subspace of that spanned by the interaction operators, selected by the environment's initial state.

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Cédric Bény. 2011-07-04. Perturbative quantum error correction. https://doi.org/10.1103/physrevlett.107.080501

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