THE EFFECT OF INTERFACE RESISTANCES ON THERMAL-WAVE PROPAGATION IN MULTILAYERED SAMPLES

In this paper a rigorous three-dimensional theoretical model describin g the temperature distribution in multi-layered samples, heated by an intensity-modulated Gaussian laser beam, is presented. The thermal int erface resistances and the thermal conductivity anisotropy of one of t he 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 th e surface temperature rise of the sample on the modulation frequency o f the excitation beam. The theoretical results can be used as a means of quantitative interpretation for the determination of interfacial th ermal resistances in layered materials with modulated photothermal tec hniques. A direct comparison between the one- and three-dimensional th eoretical models for thermal conduction in layered materials is also p resented.