Optically induced temperature variations in a two-layer volume absorber including thermal memory effects

摘要: In this paper, a theoretical model of temperature variations is derived for two-layer optically absorbing structure, including thermal memory effects. It considered that the structure surrounded by gas and illuminated on front side harmonically modulated laser beam. This based hyperbolic theory heat conduction Beer–Lambert's law absorption neglecting multiple optical reflections in each layer. The represents generalization current models two aspects. First, influence properties both layers accounted for, second, are regarded as volume absorbers incident light. Based model, expressions surface given discussed special type structures, irradiated coated side, which prominent configuration photoacoustic photothermal experiments. shown there exists frequency range coating cannot be neglected, especially at high-frequency becomes significant. an important result terms understanding experimentally measured response and, consequently, accurate characterizations various high reflected and/or transparent samples using these experimental techniques.