title: Dual wavelength sensing based on interacting gold nanodisk trimers.
abstract: Fabrication and surface plasmon properties of gold nanostructures consisting of periodic arrays of disk trimers are reported. Using electron beam lithography, disk diameters as small as 96 nm and gaps between disks as narrow as 10 nm have been achieved with an unprecedented degree of control and reproducibility. The disk trimers exhibit intense visible and infrared surface plasmon resonances which are studied as a function of the disk diameter and of the pitch between trimers. Based on simulations of the optical extinction spectra and of the electric near-field intensity maps, the resonances are assigned to a single trimer response and to collective surface plasmon excitations involving electromagnetic interaction between the trimers. The sensing properties of the disk trimers are investigated using various coating media. The reported results demonstrate the possible use of gold disk trimers for dual wavelength chemical sensing.
authors.affiliation: Institute for Material Research and Engineering, A*STAR, Singapore.
authors.forename: Vivian Kaixin
authors.initials: VK
authors.lastname: Lin
authors.forename: Siew Lang
authors.initials: SL
authors.lastname: Teo
authors.forename: Renaud
authors.initials: R
authors.lastname: Marty
authors.forename: Arnaud
authors.initials: A
authors.lastname: Arbouet
authors.forename: Christian
authors.initials: C
authors.lastname: Girard
authors.forename: Esther
authors.initials: E
authors.lastname: Alarcon-Llado
authors.forename: Shu Hua
authors.initials: SH
authors.lastname: Liu
authors.forename: Ming Yong
authors.initials: MY
authors.lastname: Han
authors.forename: Sudhiranjan
authors.initials: S
authors.lastname: Tripathy
authors.forename: Adnen
authors.initials: A
authors.lastname: Mlayah