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arXiv · 1004.0530

Thermal entanglement of Hubbard dimers in the nonextensive statistics

Hideo Hasegawa
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Abstract

The thermal entanglement of the Hubbard dimer (two-site Hubbard model) has been studied with the nonextensive statistics. We have calculated the auto-correlation ($O_q$), pair correlation ($L_q$), concurrence ($Γ_q$) and conditional entropy ($R_q$) as functions of entropic index $q$ and the temperature $T$. The thermal entanglement is shown to considerably depend on the entropic index. For $q < 1.0$, the threshold temperature where $Γ_q$ vanishes or $R_q$ changes its sign is more increased and the entanglement may survive at higher temperatures than for $q=1.0$. Relations among $L_q$, $Γ_q$ and $R_q$ are investigated. The physical meaning of the entropic index $q$ is discussed with the microcanonical and superstatistical approaches. The nonextensive statistics is applied also to Heisenberg dimers.

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BibTeXRIS

Hideo Hasegawa. 2010-12-24. Thermal entanglement of Hubbard dimers in the nonextensive statistics. https://doi.org/10.1016/j.physa.2010.12.033

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