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arXiv · 2012.04363

Phonon modes contribution in thermal rectification in graphene-C3B junction: A molecular dynamics study

Abstract

In this work using non-equilibrium molecular dynamics simulation we implement a series of simulation under positive and negative temperature gradient in order to investigate the thermal rectification in the graphene C3B junction GCB. The dependence of thermal rectification on temperature difference between the hot and the cold baths is obtained. The important quantity that we present here is the inplanes and out of plane phonon modes contribution in the thermal rectification. We see that the Y mode has high and positive thermal rectification while that the X and Z modes have small and negative thermal rectifications. Thermal rectification for Y mode increases sharply beyond T 30 K to 150 but for X and Z modes decrease slowly by increasing T Our results show that Y mode has major role in the thermal rectification Moreover the underlying mechanisms that leads to the thermal rectification and also Kapitza resistance at the interface are studied via the phonon density of states DOS

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Leila Kiani, Javad Hasanzadeh, Farrokh Yousefi. 2020-12-08. Phonon modes contribution in thermal rectification in graphene-C3B junction: A molecular dynamics study. https://doi.org/10.1016/j.physe.2021.114724

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