Tuning the plasmon shift and local electric field distribution of gold nanodumbbell: The effect of surface curvature transition from positive to negative

摘要: Abstract The localized surface plasmon resonance (LSPR) properties and local electric field distributions of the gold nanodumbbell are theoretically studied by using finite-difference time-domain (FDTD) calculation. decrease both positive curvature radius in spherical end negative midsection results absorption peak corresponding to longitudinal mode red shifts distinctly. However, transverse plasmonic is not sensitive change radii. physical mechanism has been illuminated studying shape transformation dependent distribution between nanorod nanodimer. It found that radii leads dumbbell-shaped particle transforming a dimer-like structure, while inter-particle coupling “hot spots” migrating from ends particle. There an associated shift LSPR. These indicate transition greatly affects charge distribution, enhancement coupling.