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arXiv · 1806.05080

Complete Optimal Convex Approximations of Qubit States under $B_2$ Distance

Xiao-Bin Liang·Bo Li·Biao-Liang Ye·Shao-Ming Fei·XianQing Li-Jost
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Abstract

We consider the optimal approximation of arbitrary qubit states with respect to an available states consisting the eigenstates of two of three Pauli matrices, the $B_2$-distance of an arbitrary target state. Both the analytical formulae of the $B_2$-distance and the corresponding complete optimal decompositions are obtained. The tradeoff relations for both the sum and the squared sum of the $B_2$-distances have been analytically and numerically investigated.

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Xiao-Bin Liang, Bo Li, Biao-Liang Ye, Shao-Ming Fei, XianQing Li-Jost. 2018-06-13. Complete Optimal Convex Approximations of Qubit States under $B_2$ Distance. https://doi.org/10.1007/s11128-018-1948-0

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