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arXiv · 1007.4611

Graph state basis for Pauli Channels

Xiao-yu Chen·Li-zhen Jiang
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Abstract

We introduce graph state basis diagonalization to calculate the coherent information of a quantum code passing through a Pauli channel. The scheme is 5000 times faster than the best known one for some concatenated repetition codes, providing us a practical constructive way of approaching the quantum capacity of a Pauli channel. The calculation of the coherent information of non-additive quantum code can also be greatly simplified in graph state basis.

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Xiao-yu Chen, Li-zhen Jiang. 2010-07-27. Graph state basis for Pauli Channels. https://doi.org/10.1103/physreva.83.052316

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