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arXiv · 0905.3792

Negative differential thermal resistance induced by ballistic transport

Wei-Rong Zhong·Ping Yang·Bao-Quan Ai·Zhi-Gang Shao·Bambi Hu
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Abstract

Using nonequilibrium molecular-dynamics simulations, we study the temperature dependence of the negative differential thermal resistance that appears in two-segment Frenkel-Kontorova lattices. We apply the theoretical method based on Landauer equation to obtain the relationship between the heat current and the temperature, which states a fundamental interpretation about the underlying physical mechanism of the negative differential thermal resistance. The temperature profiles and transport coefficients are demonstrated to explain the crossover from diffusive to ballistic transport. The finite-size effect is also discussed.

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Wei-Rong Zhong, Ping Yang, Bao-Quan Ai, Zhi-Gang Shao, Bambi Hu. 2009-05-23. Negative differential thermal resistance induced by ballistic transport. https://doi.org/10.1103/physreve.79.050103

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