Unconditional Security with Decoherence-Free Subspaces

Elloá B. Guedes; Francisco M. de Assis

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arXiv · 1204.3000

Unconditional Security with Decoherence-Free Subspaces

Elloá B. Guedes·Francisco M. de Assis

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Abstract

We show how to use decoherence-free subspaces over collective-noise quantum channels to convey classical information in perfect secrecy. We argue that codes defined over decoherence-free subspaces are codes for quantum wiretap channels in which the gain of information by a non-authorized receiver is zero. We also show that if some symmetry conditions are guaranteed, the maximum rate on which these secret communications take place is equal to the Holevo-Schumacher-Westmoreland capacity of the quantum channel.

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Elloá B. Guedes, Francisco M. de Assis. 2012-04-13. Unconditional Security with Decoherence-Free Subspaces. https://arxiv.org/abs/1204.3000

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