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Magnetic Susceptibility as a Macrosopic Entaglement Witness

M. Wiesniak·V. Vedral·C. Brukner
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Abstract

We show that magnetic susceptibility can reveal spin entanglement between individual constituents of a solid, while magnetisation describes their local properties. We then show that these two thermodynamical quantities satisfy complementary relation in the quantum-mechanical sense. It describes sharing of (quantum) information in the solid between spin entanglement and local properties of its individual constituents. Magnetic susceptibility is shown to be a macroscopic spin entanglement witness that can be applied without complete knowledge of the specific model (Hamiltonian) of the solid.

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M. Wiesniak, V. Vedral, C. Brukner. 2006-02-13. Magnetic Susceptibility as a Macrosopic Entaglement Witness. https://doi.org/10.1088/1367-2630%2F7%2F1%2F258

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