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arXiv · 2006.08822

Optimal approximations of available states and a triple uncertainty relation

Xiao-Bin Liang·Bo Li·Liang Huang·Biao-Liang Ye·Shao-Ming Fei·Shi-Xiang Huang
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Abstract

We investigate the optimal convex approximation of the quantum state with respect to a set of available states. By isometric transformation, we have presented the general mathematical model and its solutions together with a triple uncertainty equality relation. Meanwhile, we show a concise inequality criterion for decomposing qubit mixed states. The new results include previous ones as special cases. Our model and method may be applied to solve similar problems in high-dimensional and multipartite scenarios

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Xiao-Bin Liang, Bo Li, Liang Huang, Biao-Liang Ye, Shao-Ming Fei, Shi-Xiang Huang. 2020-06-15. Optimal approximations of available states and a triple uncertainty relation. https://doi.org/10.1103/physreva.101.062106

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