Title

Altering infrared metamaterial performance through metal resonance damping

Authors

Authors

J. Ginn; D. Shelton; P. Krenz; B. Lail;G. Boreman

Comments

Authors: contact us about adding a copy of your work at STARS@ucf.edu

Abbreviated Journal Title

J. Appl. Phys.

Keywords

FREQUENCY-SELECTIVE SURFACES; REFLECTARRAY; ELEMENTS; DESIGN; Physics, Applied

Abstract

Infrared metamaterial design is a rapidly developing field and there are increasing demands for effective optimization and tuning techniques. One approach to tuning is to alter the material properties of the metals making up the resonant metamaterial to purposefully introduce resonance frequency and bandwidth damping. Damping in the infrared portion of the spectrum is unique for metamaterials because the frequency is on the order of the inverse of the relaxation time for most noble metals. Metals with small relaxation times exhibit less resonance frequency damping over a greater portion of the infrared than metals with a longer relaxation time and, subsequently, larger dc conductivity. This leads to the unexpected condition where it is possible to select a metal that simultaneously increases a metamaterial's bandwidth and resonance frequency without altering the geometry of the structure. Starting with the classical microwave equation for thin-film resistors, a practical equivalent-circuit model is developed predicting the sensitivity of infrared metamaterials to complex film impedance. Several full-wave electromagnetic models are developed to validate the resonant-circuit model, and excellent agreement is demonstrated between modeled and measured results. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3093698]

Journal Title

Journal of Applied Physics

Volume

105

Issue/Number

7

Publication Date

1-1-2009

Document Type

Article

Language

English

First Page

8

WOS Identifier

WOS:000266633500072

ISSN

0021-8979

Share

COinS