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arXiv · 1503.03316

NMR dynamics of quantum discord for spin-carrying gas molecules in a closed nanopore

M. A. Yurischev
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Abstract

A local orthogonal transformation that transforms any centrosymmetric (CS) matrix of fourth order to the X form is found. A picewise-analytic-numerical formula Q=min{Q_π/2,Q_θ,Q_0}, where Q_π/2 and Q_0 are analytical expressions and the branch Q_θ is found by numerical searching the optimal measurement angle θ\in(0,π/2), is proposed to calculate the quantum discord Q of general X state. The developed approaches are applied to a quantitative description of recently predicted flickerings (periodic birth and death) of the quantum-information pair correlation between nuclear 1/2 spin of atoms or molecules of a gas (for examples Xe^129) in a finite asymmetric volume in the presence of a strong magnetic field.

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M. A. Yurischev. 2015-03-11. NMR dynamics of quantum discord for spin-carrying gas molecules in a closed nanopore. https://doi.org/10.1134/s106377611411020x

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