Continuum and lattice heat currents for oscillator chains

Onuttom Narayan; A. P. Young

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arXiv · 0905.3202

Continuum and lattice heat currents for oscillator chains

Onuttom Narayan·A. P. Young

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Abstract

We show that two commonly used definitions for the heat current give different results--through the Kubo formula--for the heat conductivity of oscillator chains. The difference exists for finite chains, and is expected to be important more generally for small structures. For a chain of N particles that are tethered at the ends, the ratio of the heat conductivities calculated with the two currents differs from unity by O(1/N). For a chain held at constant pressure, the difference from unity decays more slowly, and is consistent with O(1/N^eta) with 1 > eta > 0.5.

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Onuttom Narayan, A. P. Young. 2009-05-20. Continuum and lattice heat currents for oscillator chains. https://arxiv.org/abs/0905.3202

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