Kapitza conductance of silicon-amorphous polyethylene interfaces by molecular dynamics simulations

We use nonequilibrium molecular dynamics simulation to elucidate the interfacial thermal conductance between single-crystal silicon and amorphous polyethylene. In particular, we investigate the role of solid stiffness and the bonding strength across the interface on the interfacial thermal conductance. Simulations of interfacial scattering of individual phonon wave packets indicate that neither diffuse mismatch model nor acoustic mismatch model describes the interfacial scattering process quantitatively. In general, transmission coefficients for longitudinal phonons are significantly higher than those for transverse phonons. We also observe that anharmonic processes can be important for interfacial conductance.