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Normal Heat Conductivity in a strongly pinned chain of anharmonic oscillators

R. Lefevere·A. Schenkel
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Abstract

We consider a chain of coupled and strongly pinned anharmonic oscillators subject to a non-equilibrium random forcing. Assuming that the stationary state is approximately Gaussian, we first derive a stationary Boltzmann equation. By localizing the involved resonances, we next invert the linearized collision operator and compute the heat conductivity. In particular, we show that the Gaussian approximation yields a finite conductivity $κ\sim\frac{1}{λ^2T^2}$, for $λ$ the anharmonic coupling strength.

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BibTeXRIS

R. Lefevere, A. Schenkel. 2005-11-03. Normal Heat Conductivity in a strongly pinned chain of anharmonic oscillators. https://doi.org/10.1088/1742-5468%2F2006%2F02%2Fl02001

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