title: Synthesizing low loss negative index metamaterial stacks for the mid-infrared using genetic algorithms.
abstract: Negative index metamaterial designs for the mid-infrared with low absorption and impedance mismatch losses are presented. A robust genetic algorithm is employed to optimize the flexible metamaterial structure for targeted refractive index and impedance values. A new figure of merit is introduced to evaluate the impedance match of the metamaterial to free space. Two designs are presented demonstrating low-loss characteristics for a thin metamaterial with two metal screens and a thick metamaterial stack with five screens. The device performance is analyzed when adding more screens to the structure, revealing that optimizing a thick stack produces a metamaterial with properties approaching those of a bulk material.
authors.affiliation: Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Jeremy A
authors.initials: JA
authors.lastname: Bossard
authors.forename: Seokho
authors.initials: S
authors.lastname: Yun
authors.forename: Douglas H
authors.initials: DH
authors.lastname: Werner
authors.forename: Theresa S
authors.initials: TS
authors.lastname: Mayer
mesh_terms: D000465:Algorithms; D017076:Computer-Aided Design; D004867:Equipment Design; D007094:Imides / Q000737:chemistry; D008420:Manufactured Materials; D008422:Materials Testing; D008670:Metals / Q000737:chemistry*; D008962:Models, Theoretical; D055095:Optics and Photonics; D012031:Refractometry
chemical_list: D007094:Imides; D008670:Metals