Coupled Systems Mechanics, Vol. 11, No. 5 (2022) 459-483 https://doi.org/10.12989/csm.2022.11.5.459 459 Copyright © 2022 Techno-Press, Ltd. http://www.techno-press.org/?journal=csm&subpage=8 ISSN: 2234-2184 (Print), 2234-2192 (Online) Photothermoelastic interactions under Moore-Gibson- Thompson thermoelasticity Rajneesh Kumar 1 , Nidhi Sharma 2 and Supriya Chopra 3 1 Department of Mathematics, Kurukshetra University, Kurukshetra, Haryana, India 2 Department of Mathematics, Maharishi Markandeshwar University, Mullana, Ambala, Haryana, India 3 Department of Mathematics, Government College for Women, Ambala city, Haryana, India (Received January 17, 2022, Revised July 16, 2022, Accepted July 17, 2022) Abstract. In the present work, a new photothermoelastic model based on Moore - Gibson- Thompson theory has been constructed. The governing equations for orthotropic photothermoelastic plate are simplified for two- dimension model. Laplace and Fourier transforms are employed after converting the system of equations into dimensionless form. The problem is examined due to various specified sources. Moving normal force, ramp type thermal source and carrier density periodic loading are taken to explore the application of the assumed model. Various field quantities like displacements, stresses, temperature distribution and carrier density distribution are obtained in the transformed domain. The problem is validated by numerical computation for a given material and numerical obtained results are depicted in form of graphs to show the impact of various theories of thermoelasticity along with impact of moving velocity, ramp type and periodic loading parameters. Some special cases are also explored. The results obtained in this paper can be used to design various semiconductor elements during the coupled thermal, plasma and elastic wave and other fields in the material science, physical engineering. Keywords: carrier density loading; Fourier transform; Laplace transform; Moore-Gibson-Thompson thermoelastic model; moving normal force; photothermoelastic orthotropic; ramp type thermal source 1. Introduction Analysis of mechanical and thermal interaction within a solid medium is of emended significance in various scientific fields. There are few examples such as high energy particle accelerated devices, modern aeronautical and astronomical engineering and different system exploited in nuclear and industrial applications with the consideration of second sound effect in thermoelastic model plays a significant role in analysing elastic body with in a variety of scientific and technological fields. In contradiction with physical observation the infinite thermal propagation speed is observed through conventional uncoupled theories. The coupled thermoelasticity proposed by Biot (1956) in order to eradicate the classic uncoupled principle’s inherent paradox. This paradox suggests that elastic changes have no temperature influence. The heat equations for both diffusion theories indicate that the heat wave Corresponding author, Assistant Professor, E-mail: chopra.s22@gmail.com