Enhancement of nonlinear optic effect of the second harmonic generation in plasmonic waveguide using graphene and pyramid-shape gold nanoparticles

This study introduces a novel approach to significantly enhance the Second Harmonic Generation (SHG) in plasmonic waveguides by integrating pyramid-shaped gold nanoparticles within a graphene matrix. Leveraging graphene's exceptional electrical, thermal, and optical properties, we optimize the nonlinear optical response, achieving unprecedented efficiency in SHG processes. Our investigation reveals that the geometric configuration, specifically the aspect ratio and spatial arrangement of gold nanoparticles, critically influences the magnitude of plasmonic light absorption and SHG enhancement. Furthermore, we explore the synergetic effect of incorporating a gold-silver nanoparticle alloy, demonstrating a substantial improvement in SHG performance over traditional gold nanoparticle setups. Through systematic tuning of nanoparticle characteristics and strategic material pairing, our work unveils a pathway to highly efficient, graphene-enhanced plasmonic devices for advanced optical applications, marking a significant stride in the field of nonlinear photonics.