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Suboptimal quantum-error-correcting procedure based on semidefinite programming

Naoki Yamamoto·Shinji Hara·Koji Tsumura
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Abstract

In this paper, we consider a simplified error-correcting problem: for a fixed encoding process, to find a cascade connected quantum channel such that the worst fidelity between the input and the output becomes maximum. With the use of the one-to-one parametrization of quantum channels, a procedure finding a suboptimal error-correcting channel based on a semidefinite programming is proposed. The effectiveness of our method is verified by an example of the bit-flip channel decoding.

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Naoki Yamamoto, Shinji Hara, Koji Tsumura. 2006-06-13. Suboptimal quantum-error-correcting procedure based on semidefinite programming. https://doi.org/10.1103/physreva.71.022322

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