title: Tunable plasmonic response from alkanethiolate-stabilized gold nanoparticle superlattices: evidence of near-field coupling.
abstract: We report on the self-assembly of large-area, highly ordered 2D superlattices of alkanethiolate-stabilized gold nanoparticles ( approximately 10.5 nm in core diameter) onto quartz substrates with varying lattice constants, which can be controlled by the alkyl chain lengths, ranging from C12 (1-dodecanethiolate), C14 (1-tetradecanethiolate), C16 (1-hexadecanethiolate), to C18 (1-octadecanethiolate). These 2D nanoparticle superlattices exhibit strong collective surface plasmon resonance that is tunable via the near-field coupling of adjacent nanoparticles. The approach presented here provides a unique and viable means of building artificial "plasmonic crystals" with precisely designed optical properties, which can be useful for the emerging fields of plasmonics, such as subwavelength integrated optics.
authors.affiliation: Institute of Nanoengineering and Microsystems and Department of Physics, National Tsing-Hua University, Hsinchu 30013, Taiwan, Republic of China.
authors.forename: Chi-Fan
authors.initials: CF
authors.lastname: Chen
authors.forename: Shien-Der
authors.initials: SD
authors.lastname: Tzeng
authors.forename: Hung-Ying
authors.initials: HY
authors.lastname: Chen
authors.forename: Kuan-Jiuh
authors.initials: KJ
authors.lastname: Lin
authors.forename: Shangjr
authors.initials: S
authors.lastname: Gwo