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Fidelity of a t-error correcting quantum code with more than t errors

Ryutaroh Matsumoto
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Abstract

It is important to study the behavior of a t-error correcting quantum code when the number of errors is greater than t, because it is likely that there are also small errors besides t large correctable errors. We give a lower bound for the fidelity of a t-error correcting stabilizer code over a general memoryless channel, allowing more than t errors. We also show that the fidelity can be made arbitrary close to 1 by increasing the code length.

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Ryutaroh Matsumoto. 2001-05-11. Fidelity of a t-error correcting quantum code with more than t errors. https://doi.org/10.1103/physreva.66.059901

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