Localized surface plasmon resonance characteristics of gold dimeric nanobipyramids

Dimer is a new type of nanostructure that has attracted much attention due to its ability to achieve more significant field strength enhancement effects through the interaction of two nanoparticles than monomers. This paper applies the dimer structure to gold nanobipyramids particles with unique tip structures. The localized surface plasmon resonance (LSPR) properties of the gold dimeric nanobipyramids are simulated using the finite difference time domain method. The results show that the gold dimeric nanobipyramids achieves several times higher field enhancement in the nanogap compared with the gold monomer nanobipyramids. At the same time, under the same conditions, its electric field intensity is significantly higher than that of the gold dimeric nanospheres and gold dimeric nanorods. Furthermore, by varying the gap, sharpness, and surrounding medium, the changes in the LSPR effects of the gold dimeric nanobipyramids under different conditions were calculated. The research shows that by tuning the structure, morphology, and surrounding medium of the dimeric nanobipyramids, higher extinction intensity, more intensity field enhancement, and greater sensitivity can be achieved, offering significant application prospects in various optoelectronic device fields. This work has significant reference value for studying the LSPR characteristics of dimeric metal nanoparticles and their related applications.