The effect of interface resistances on thermal wave propagation in multi-layered samples

In this paper a rigorous three-dimensional theoretical model describing the temperature distribution in multi-layered samples, heated by an intensity-modulated Gaussian laser beam, is presented. The thermal interface resistances and the thermal conductivity anisotropy of one of the layers are taken into consideration. The three-dimensional thermal diffusion model is used to investigate the effect of thermal interface resistances on thermal conduction in three-layered samples, which is monitored in terms of the dependences of the amplitude and phase of the surface temperature rise of the sample on the modulation frequency of the excitation beam. The theoretical results can be used as a means of quantitative interpretation for the determination of interfacial thermal resistances in layered materials with modulated photothermal techniques. A direct comparison between the one- and three-dimensional theoretical models for thermal conduction in layered materials is also presented.