Photothermal diffusion in nonsimple semiconductor strips: Impact of moving heat sources and acoustic pressure via memory and nonlocality effects

This study introduces a novel dual-phase lag model for semiconductor materials, advancing the field of photothermal diffusion (PTD) by integrating memory effects and spatiotemporal nonlocality. Unlike conventional approaches, it employs a modified nonsimple photoexcitation framework to derive governing equations for heat conduction during optical transport processes, particularly under the influence of internal moving heat sources. One of the study's major contributions is its ability to model the interconnected dynamics of thermal, mechanical-elastic, plasma, and acoustic wave propagation in nonsimple semiconductor thin strips. The research employs an analytical framework, combining the Laplace transform method with an operational methodology, to simplify complex differential equations into solvable algebraic forms, enabling efficient modeling of multi-physics interactions. To achieve precise space-time solutions, the study employs the Gaver–Stehfest inversion formula with Salzer summation for the numerical inversion of the Laplace transform. Key findings include demonstrating the influence of moving heat sources and acoustic pressure on material behavior and highlighting the critical roles of memory effects and nonlocal phenomena. The model further provides insights into how sectional acoustic, plasma, and thermomechanical sources affect a finite-length strip, underscoring its versatility. By using silicon as a representative material, the study graphically illustrates the profound impacts of photoexcitation, heat source dynamics, and wave interactions. This work bridges gaps in existing thermoelastic models, offering a comprehensive framework for studying multi-physical interactions in semiconductors and paving the way for future research and technological advancements.