Differential evolution-optimized Ni–graphene metasurface solar absorber

This paper presents a Differential Evolution (DE)-optimized Ni–graphene–AlN metasurface solar absorber designed for efficient light trapping across the 300–850[Formula: see text]THz (visible–NIR) range. The multilayer architecture, consisting of nickel rod resonators, an aluminum nitride dielectric spacer, and a graphene interlayer, was optimized using a DE algorithm that simultaneously tuned the thicknesses of all layers to maximize broadband absorption. The optimized design achieves an average absorption of 98.17%, representing a 10.17% improvement over the initial configuration. Electric field analysis reveals hybrid plasmonic coupling between localized surface plasmons in the Ni rod resonators and surface plasmon polaritons in graphene, leading to strong field confinement and impedance matching. The absorber exhibits polarization-insensitive and angularly robust performance up to [Formula: see text] and achieves approximately 45% lower computational cost than exhaustive parametric sweeps, demonstrating both high efficiency and optimization scalability.