title: Focussing light through a stack of toroidal channels in PMMA.
abstract: We propose a transformational design of an axi-symmetric gradient lens for electromagnetic waves. We show that a metamaterial consisting of toroidal air channels of diameters ranging from 23 nm to 190 nm in a matrix of Polymethylmethacrylate (PMMA) allows for a focussing effect of light over a large bandwidth i.e. [600-1000] nm. We finally propose a simplified design of lens allowing for a two-photon lithography implementation.
authors.affiliation: Institut Fresnel, UMR CNRS 6133, Aix-Marseille Université, Campus universitaire de Saint-Jérôme, 13397 Marseille, France.
authors.forename: Tieh-Ming
authors.initials: TM
authors.lastname: Chang
authors.forename: Sebastien
authors.initials: S
authors.lastname: Guenneau
authors.forename: Jérôme
authors.initials: J
authors.lastname: Hazart
authors.forename: Stefan
authors.initials: S
authors.lastname: Enoch