In photoacoustic effect, the solid sample absorbs a fraction of the radiation falling upon it and excitation process occurs. The type of excitation depends on the energy of the incident radiation. The relaxation processes, which are also popularly known as non-radiative de-excitation processes generally take place. The light – matter interaction is responsible for the generation of heat within the solid sample. The temperature of the sample changes due to absorption and non-radiative relaxation by the atoms. The pressure fluctuations will be generated due to the heating and cooling of the sample. Today, crystalline solids are widely studied due to their wide scientific and industrial applications. Temperature is one of the important parameter to be studied regarding artificial preparation of large crystals. In this paper, transient translational temperature on the surface of a homogeneous isotropic cubic crystal kept in a photoacoustic cell is calculated theoretically. For a simple cubic homogeneous crystal kept in a photoacoustic cell, an airy stress function is determined based on laser interaction with surface of the crystal. By applying the finite Marchi-Fasulo integral transform method within the crystal size limitations, transient translational temperature is exactly determined.
Heat flux balance description of unidirectional freezing and melting dynamics on a translational temperature gradient stage
