Quantum-modified photo-thermoelastic wave propagation in semiconductors with temperature-dependent thermal conductivity

Abstract

A generalized quantum-modified photo-thermoelastic model is developed to investigate wave propagation in semiconductor media subjected to ramp-type laser heating while accounting for temperature-dependent thermal conductivity. The model incorporates variable thermal conductivity into the heat equation and introduces quantum carrier transport through a density-gradient correction, enabling a more realistic description of the coupled interactions between elastic deformation, thermal diffusion, and photo-generated carrier dynamics. Using the normal-mode analytical technique, closed-form solutions and dispersion characteristics are derived for a two-dimensional semiconductor medium. The analysis demonstrates that variable thermal conductivity significantly redistributes thermal energy, resulting in smoother temperature gradients and reduced thermoelastic stress localization compared with classical constant-conductivity models. In addition, quantum carrier diffusion further enhances wave attenuation and suppresses carrier accumulation near the surface, leading to more stable thermo-mechanical responses under laser excitation. The combined effects of temperature-dependent thermal conductivity and quantum carrier transport are shown to play a critical role in controlling thermoelastic wave propagation in semiconductor materials. These findings provide new insights into coupled thermal-mechanical-electronic interactions in laser-excited semiconductors and offer a useful theoretical framework for the design of surface acoustic wave devices, optoelectronic sensors, and micro- and nano-scale thermal management technologies.