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Thermal conductance of the coupled-rotator chain: Influence of temperature and size

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 نشر من قبل Constantino Tsallis
 تاريخ النشر 2017
  مجال البحث فيزياء
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Thermal conductance of a homogeneous 1D nonlinear lattice system with neareast neighbor interactions has recently been computationally studied in detail by Li et al [Eur. Phys. J. B {bf 88}, 182 (2015)], where its power-law dependence on temperature $T$ for high temperatures is shown. Here, we address its entire temperature dependence, in addition to its dependence on the size $N$ of the system. We obtain a neat data collapse for arbitrary temperatures and system sizes, and numerically show that the thermal conductance curve is quite satisfactorily described by a fat-tailed $q$-Gaussian dependence on $TN^{1/3}$ with $q simeq 1.55$. Consequently, its $T toinfty$ asymptotic behavior is given by $T^{-alpha}$ with $alpha=2/(q-1) simeq 3.64$.



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