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Thermal entanglement in the nanotubular system Na_2V_3O_7

T. Vértesi·E. Bene
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Abstract

Macroscopic entanglement witnesses have been put forward recently to reveal nonlocal quantum correlations between individual constituents of the solid at nonzero temperatures. Here we apply a recently proposed universal entanglement witness, the magnetic susceptibility [New J. Phys. {\bf 7}, 258 (2005)] for the estimation of the critical temperature $T_c$ in the nanotubular system ${\rm Na_2V_3O_7}$ below which thermal entanglement is present. As a result of an analysis based on the experimental data for dc-magnetic susceptibility, we show that $T_c \approx 365$ K, which is approximately three times higher than the critical temperature corresponding to the bipartite entanglement.

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T. Vértesi, E. Bene. 2006-05-24. Thermal entanglement in the nanotubular system Na_2V_3O_7. https://doi.org/10.1103/physrevb.73.134404

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