title: Chemically tailored dielectric-to-metal transition for the design of metamaterials from nanoimprinted colloidal nanocrystals.
abstract: We demonstrate optical metamaterial design using colloidal gold nanocrystal building blocks. In the solid state, chemically exchanging the nanocrystals' surface-capping molecules provides a tailorable dielectric-to-metal transition exhibiting a 10(10) range in DC conductivity and dielectric permittivity ranging from everywhere positive to everywhere negative throughout the visible-to-near-IR. Direct, wide-area nanoimprinting of subwavelength superstructures at room temperature, on plastic and glass substrates, affords plasmonic resonances ranging from 660 to 1070 nm, in agreement with numerical simulations.
authors.affiliation: Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Aaron T
authors.initials: AT
authors.lastname: Fafarman
authors.forename: Sung-Hoon
authors.initials: SH
authors.lastname: Hong
authors.forename: Humeyra
authors.initials: H
authors.lastname: Caglayan
authors.forename: Xingchen
authors.initials: X
authors.lastname: Ye
authors.forename: Benjamin T
authors.initials: BT
authors.lastname: Diroll
authors.forename: Taejong
authors.initials: T
authors.lastname: Paik
authors.forename: Nader
authors.initials: N
authors.lastname: Engheta
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Murray
authors.forename: Cherie R
authors.initials: CR
authors.lastname: Kagan