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arXiv · 1111.6383

Small perturbation of a disordered harmonic chain by a noise and an anharmonic potential

Cédric Bernardin·François Huveneers
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Abstract

We study the thermal properties of a pinned disordered harmonic chain weakly perturbed by a noise and an anharmonic potential. The noise is controlled by a parameter $λ\rightarrow 0$, and the anharmonicity by a parameter $λ' \le λ$. Let $κ$ be the conductivity of the chain, defined through the Green-Kubo formula. Under suitable hypotheses, we show that $κ= \mathcal O (λ)$ and, in the absence of anharmonic potential, that $κ\sim λ$. This is in sharp contrast with the ordered chain for which $κ\sim 1/λ$, and so shows the persitence of localization effects for a non-integrable dynamics.

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Cédric Bernardin, François Huveneers. 2013-10-05. Small perturbation of a disordered harmonic chain by a noise and an anharmonic potential. https://arxiv.org/abs/1111.6383

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