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arXiv · 2108.01961

Heat transport in nonlinear lattices free from the Umklapp process

Kazuyuki Yoshimura·Yusuke Doi·Tomoya Kitamura
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Abstract

We construct one-dimensional nonlinear lattices having the special property such that the Umklapp process vanishes and only the normal processes are included in the potential functions. These lattices have long-range quartic nonlinear and nearest neighbor harmonic interactions with/without harmonic on-site potential. We study heat transport in two cases of the lattices with and without harmonic on-site potential by non-equilibrium molecular dynamics simulation. It is shown that the ballistic heat transport occurs in both cases, i.e., the scaling law $κ\propto N$ holds between the thermal conductivity $κ$ and the lattice size $N$. This result directly validates Peierls's hypothesis that only the Umklapp processes can cause the thermal resistance while the normal one do not.

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Kazuyuki Yoshimura, Yusuke Doi, Tomoya Kitamura. 2021-12-14. Heat transport in nonlinear lattices free from the Umklapp process. https://doi.org/10.1103/physreve.105.024140

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