Analysis on Thermal Boundary Resistance at the Interfaces in Superlattices by Using the Molecular Dynamics

분자동역학법을 이용한 초격자 내부의 경계면 열저항의 해석

From the viewpoint of a macro state, there is no thermal boundary resistance (TBR) at an interface if both surfaces at an interface are perfectly contacted. However, recent molecular dynamics (MD) studies reported that there still exists the TDR at the interface in an ideal epitaxial superlttice. Our previous studies suggested the model to predict the TBR not only quantitatively also qualitatively in superlattices. The suggested model was based on the classical theory of a wave reflection, and provided highly satisfactory results for an engineering purpose. However, it was not the complete model because our previous model was derived by considering only the effects from a mass ratio and a potential ratio of two species. The interaction of two species presented by the Lennard-Jones (L-J) potential is governed by the mutual ratio of the masses, the potential well depths, and the diameters. In this study, we performed the preliminary simulations to investigate the effect resulting from the diameter ratio of two species for the completion of our model and confirmed that it was also a ruling factor to the TBR at an interface in superlattices.