title: Size-dependent permittivity and intrinsic optical anisotropy of nanometric gold thin films: a density functional theory study.
abstract: Physical properties of materials are known to be different from the bulk at the nanometer scale. In this context, the dependence of optical properties of nanometric gold thin films with respect to film thickness is studied using density functional theory (DFT). We find that the in-plane plasma frequency of the gold thin film decreases with decreasing thickness and that the optical permittivity tensor is highly anisotropic as well as thickness dependent. Quantitative knowledge of planar metal film permittivity's thickness dependence can improve the accuracy and reliability of the designs of plasmonic devices and electromagnetic metamaterials. The strong anisotropy observed may become an alternative method of realizing indefinite media.
authors.affiliation: Department of Material Science and Engineering, University of Arizona, 1235 E James E Roger Way, Tucson, AZ 85721, USA.
authors.forename: Slimane
authors.initials: S
authors.lastname: Laref
authors.forename: Jiangrong
authors.initials: J
authors.lastname: Cao
authors.forename: Abu
authors.initials: A
authors.lastname: Asaduzzaman
authors.forename: Keith
authors.initials: K
authors.lastname: Runge
authors.forename: Pierre
authors.initials: P
authors.lastname: Deymier
authors.forename: Richard W
authors.initials: RW
authors.lastname: Ziolkowski
authors.forename: Mamoru
authors.initials: M
authors.lastname: Miyawaki
authors.forename: Krishna
authors.initials: K
authors.lastname: Muralidharan
mesh_terms: D016880:Anisotropy; D003198:Computer Simulation; D025802:Electric Capacitance; D006046:Gold / Q000737:chemistry*; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D008956:Models, Chemical; D012031:Refractometry
chemical_list: D008567:Membranes, Artificial; D006046:Gold