Interacted electron and phonon thermal waves in semiconductors: application to photothermal effects

In this work heat transport in condensed media is examined from the theoretical point of view. We consider the heat flux at the surface of the sample as boundary condition and a fixed temperature on the other surface of the sample those boundary conditions reflect the usual experimental conditions in photoacoustic experiments. From this, we obtain explicitly the electron and phonon temperature distributions in the sample as function of both, time and position, valid for all range of the laser chopper frequency. The characterization of the thermal waves properties is discussed and some practical procedures for this purpose provide us with information about the electron and phonon thermal parameters.