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arXiv · 0908.2838

Entanglement temperature in molecular magnets composed of S-spin dimers

D. O. Soares-Pinto·A. M. Souza·R. S. Sarthour·I. S. Oliveira·M. S. Reis·P. Brandao·J. Rocha·A. M. dos Santos
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Abstract

In the present work, we investigate the quantum thermal entanglement in molecular magnets composed of dimers of spin $S$, using an Entanglement Witness built from measurements of magnetic susceptibility. An entanglement temperature, $T_{e}$, is then obtained for some values of spin $S$. From this, it is shown that $T_{e}$ is proportional to the intradimer exchange interaction $J$ and that entanglement appears only for antiferromagnetic coupling. The results are compared to experiments carried on three isostructural materials: KNaMSi$_{4}$O$_{10}$ (M$=$Mn, Fe or Cu).

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D. O. Soares-Pinto, A. M. Souza, R. S. Sarthour, I. S. Oliveira, M. S. Reis, P. Brandao, J. Rocha, A. M. dos Santos. 2009-08-20. Entanglement temperature in molecular magnets composed of S-spin dimers. https://doi.org/10.1209/0295-5075/87/40008

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