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arXiv · 0912.3416

Thermal conductivity of the Toda lattice with conservative noise

Alessandra Iacobucci·Frederic Legoll·Stefano Olla·Gabriel Stoltz
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Abstract

We study the thermal conductivity of the one dimensional Toda lattice perturbed by a stochastic dynamics preserving energy and momentum. The strength of the stochastic noise is controlled by a parameter $γ$. We show that heat transport is anomalous, and that the thermal conductivity diverges with the length $n$ of the chain according to $κ(n) \sim n^α$, with $0 < α\leq 1/2$. In particular, the ballistic heat conduction of the unperturbed Toda chain is destroyed. Besides, the exponent $α$ of the divergence depends on $γ$.

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Alessandra Iacobucci, Frederic Legoll, Stefano Olla, Gabriel Stoltz. 2009-12-17. Thermal conductivity of the Toda lattice with conservative noise. https://doi.org/10.1007/s10955-010-9996-6

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