Reflection of photothermoelastic waves in a semiconductor material with different relaxations

In this article, reflection of thermoelastic waves in semiconducting medium is studied. The selected elastic medium is a half-space with an exponentially decaying heat source. Firstly, the governing equations are formulated with the help of generalized thermoelastic model initiated by Green and Lindsay. Interface of the solid is exposed to a heat flow having an exponentially decaying pulse. Harmonic wave solution is adopted to find the solution. It is found that, for the selected half-space model, four types of coupled waves are generated after reflection, namely quasi-longitudinal wave Pq, quasi-transverse wave SVq, quasi-thermal wave Tq, and quasi-plasma wave PLq. Different characteristics of waves subjected to angular frequency of incident wave are calculated numerically for the medium. Effect of the incident angle on amplitudes of reflected waves has also been calculated in terms of amplitude ratios for a semiconductor like material. Comparison of results obtained in the context three different models of thermoelastic theories is also presented, and the findings are highlighted. (author)