Thermal transport in S-shaped graphene nano-junctions

By using nonequilibrium Greenʹs function method, we study the phonon transport properties in S-shaped graphene nano-junctions (GNJs). Interesting transmission phenomenon is found. The transmission spectrum of low frequency phonon shows forbidden frequency band, by changing the width W2 of the S-shaped GNJs. These low frequency forbidden bands are sensitive to their periodic geometric shape of GNJs. These thermal transport phenomena can be explained by analyzing the phonon transmission coefficient. This paper illustrates the thermal transport mechanisms in the different S-shaped GNJs, and the results could provide significant physical models and theoretical validity in designing the thermal devices based on the GNJs.