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arXiv · 1101.4530

Thermal conductivity of nonlinear waves in disordered chains

Sergej Flach·Mikhail Ivanchenko·Nianbei Li
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Abstract

We present computational data on the thermal conductivity of nonlinear waves in disordered chains. Disorder induces Anderson localization for linear waves and results in a vanishing conductivity. Cubic nonlinearity restores normal conductivity, but with a strongly temperature-dependent conductivity $\kappa(T)$. We find indications for an asymptotic low-temperature $\kappa \sim T^4$ and intermediate temperature $\kappa \sim T^2$ laws. These findings are in accord with theoretical studies of wave packet spreading, where a regime of strong chaos is found to be intermediate, followed by an asymptotic regime of weak chaos (EPL 91 (2010) 30001).

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Sergej Flach, Mikhail Ivanchenko, Nianbei Li. 2011-01-24. Thermal conductivity of nonlinear waves in disordered chains. https://doi.org/10.1007/s12043-011-0186-0

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