Thermal boundary resistance at the interface between a crystal and a disordered solid

The thermal boundary resistance at the interface between a crystalline and a disordered solid with large scattering mismatch but negligible acoustic mismatch is calculated. Under the assumption that phonon scattering in the disordered material is predominantly elastic and strongly frequency dependent, the thermal boundary resistance derives from the spectral redistribution of the heat current by inelastic processes in the vicinity of the interface.