title: Tailorable plasmonic circular dichroism properties of helical nanoparticle superstructures.
abstract: We utilize a peptide-based methodology to prepare a diverse collection of double-helical gold nanoparticle superstructures having controllable handedness and structural metrics. These materials exhibit well-defined circular dichroism signatures at visible wavelengths owing to the collective dipole-dipole interactions between the nanoparticles. We couple theory and experiment to show how tuning the metrics and structure of the helices results in predictable and tailorable chirooptical properties. Finally, we experimentally and theoretically demonstrate that the intensity, position, and nature of the chirooptical activity can be carefully adjusted via silver overgrowth. These studies illustrate the utility of peptide-based nanoparticle assembly platforms for designing and preparing complex plasmonic materials with tailorable optical properties.
authors.affiliation: Department of Chemistry, University of Pittsburgh , 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.
authors.forename: Chengyi
authors.initials: C
authors.lastname: Song
authors.forename: Martin G
authors.initials: MG
authors.lastname: Blaber
authors.forename: Gongpu
authors.initials: G
authors.lastname: Zhao
authors.forename: Peijun
authors.initials: P
authors.lastname: Zhang
authors.forename: H Christopher
authors.initials: HC
authors.lastname: Fry
authors.forename: George C
authors.initials: GC
authors.lastname: Schatz
authors.forename: Nathaniel L
authors.initials: NL
authors.lastname: Rosi