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arXiv · 1110.4942

Anomalous negative differential thermal resistance in a momentum-conserving lattice

Wei-Rong Zhong·Mao-Ping Zhang·Bao-Quan Ai·Bambi Hu
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Abstract

A two-segment Fermi-Pasta-Ulam lattices has been investigated by using nonequilibrium molecular dynamics. Here we present an anomalous negative differential thermal resistance (NDTR) that have not been reported in Frenkel-Kontorova and ϕ_4 lattices up to the present. The NDTR disappears at low temperature region. The region of NDTR shifts from the large to the small temperature difference region as the system size increases. Anomalous dependence of NDTR on the temperature can be explained as the negative effect induced by the nonlinear coupling. The explanation can also cover the phenomenon of NDTR in momentum-nonconserved lattices.

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Wei-Rong Zhong, Mao-Ping Zhang, Bao-Quan Ai, Bambi Hu. 2011-10-22. Anomalous negative differential thermal resistance in a momentum-conserving lattice. https://doi.org/10.1103/physreve.84.031130

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