title: Hybridized plasmon modes and near-field enhancement of metallic nanoparticle-dimer on a mirror.
abstract: For the attractive plasmonic structure consisting of metal nanoparticles (NPs) on a mirror, the coexistence of near-field NP-NP and NP-mirror couplings is numerically studied at normal incidence. By mapping their 3D surface charge distributions directly, we have demonstrated two different kinds of mirror-induced bonding dipole plasmon modes and confirmed the bonding hybridizations of the mirror and the NP-dimer which may offer a much stronger near-field enhancement than that of the isolated NP dimers over a broad wavelength range. Further, it is revealed that the huge near-field enhancement of these two modes exhibit different dependence on the NP-NP and NP-mirror hot spots, while both of their near-field resonance wavelengths can be tuned to the blue exponentially by increasing the NP-NP gaps or the NP-mirror separation. Our results here benifit significantly the fundamental understanding and practical applications of metallic NPs on a mirror in plasmonics.
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Lingwei
authors.initials: L
authors.lastname: Ma
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Mengjing
authors.initials: M
authors.lastname: Hou
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Jianghao
authors.initials: J
authors.lastname: Li
authors.affiliation: High-Tech Institute of Xi'an, Shaanxi 710025, P. R. China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Xie
authors.affiliation: Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Zhengjun
authors.initials: Z
authors.lastname: Zhang