Dual-fractional nonlocal photo-thermoelastic waves in microelongated semiconductor metamaterial interfaces with variable thermal conductivity

Purpose Unlike previous studies that investigated these mechanisms individually, the present work establishes a unified analytical formulation that elucidates their mutual interaction and reveals new coupled wave characteristics arising from the simultaneous effects of thermal memory, nonlocality, variable thermal conductivity and carrier transport. Design/methodology/approach This work presents a theoretical investigation of coupled photo-thermoelastic wave propagation across a semiconductor metamaterial interface by developing a generalized model that combines nonlocal microelongation elasticity, dual-fractional heat conduction, carrier diffusion and variable thermal conductivity. Unlike recent studies that have primarily examined these mechanisms individually or in partially coupled formulations, the present model examines their combined influence on transient multiphysics wave propagation at semiconductor interfaces. Findings These results provide physically verifiable insights into the relative roles of spatial interactions and thermal memory in controlling thermoelastic wave propagation and suggest practical design strategies for improving the thermal management and mechanical reliability of semiconductor heterostructures, photonic devices and MEMS/NEMS components subjected to ultrafast thermal loading. Originality/value The governing equations are transformed into a dimensionless form and solved analytically using the normal mode method. Numerical results are presented for displacement, temperature, carrier density, microelongation, heat flux and normal stress distributions. The analysis demonstrates that nonlocality primarily suppresses stress concentration and smooths field gradients near the interface; variable thermal conductivity modifies the heat penetration depth and transient temperature distribution, whereas dual-fractional thermal memory governs wave attenuation, phase delay and propagation speed. Their combined interaction produces a coupled dispersive-dissipative response that cannot be predicted by classical thermoelastic formulations or by models neglecting carrier transport or microstructural effects.