title: Near-field Raman imaging and electromagnetic field confinement in the self-assembled monolayer array of gold nanoparticles.
abstract: Spatial distribution of surface enhanced Raman activity is visualized for two-dimensional (2D) nearly close-packed and well-ordered monolayer array of gold nanoparticles by using scanning near-field optical microscope. The 2D arrays exhibit highly nonuniform enhancement in Raman scattering, i.e., the regions along the edge of the 2D array are preferentially enhanced. We demonstrate that the spatial distribution of the localized electric field is also nonuniform and agrees well with that of the Raman enhancement.
authors.affiliation: Department of Applied Physics, National Defense Academy, Yokosuka, Kanagawa 239-0811, Japan.
authors.forename: Mohammad Kamal
authors.initials: MK
authors.lastname: Hossain
authors.forename: Toru
authors.initials: T
authors.lastname: Shimada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kitajima
authors.forename: Kohei
authors.initials: K
authors.lastname: Imura
authors.forename: Hiromi
authors.initials: H
authors.lastname: Okamoto