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Exponential lower bound on the highest fidelity achievable by quantum error-correcting codes

Mitsuru Hamada
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Abstract

On a class of memoryless quantum channels which includes the depolarizing channel, the highest fidelity of quantum error-correcting codes of length n and rate R is proven to be lower bounded by 1-exp[-nE(R)+o(n)] for some function E(R). The E(R) is positive below some threshold R', which implies R' is a lower bound on the quantum capacity.

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Mitsuru Hamada. 2002-06-21. Exponential lower bound on the highest fidelity achievable by quantum error-correcting codes. https://doi.org/10.1103/physreva.65.052305

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