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Title: Perfect terahertz absorber using fishnet based metafilm

We present a perfect terahertz (THz) absorber working for a broad-angle of incidence. The two fold symmetry of rectangular fishnet structure allows either complete absorption or mirror like reflection depending on the polarization of incident the THz beam. Metamaterials enable the ability to control the electromagnetic wave in a unique fashion by designing the permittivity or permeability of composite materials with desired values. Although the initial idea of metamaterials was to obtain a negative index medium, however, the evolution of metamaterials (MMs) offers a variety of practically applicable devices for controlling electromagnetic wave such as tunable filters, modulators, phase shifters, compact antenna, absorbers, etc. Terahertz regime, a crucial domain of the electromagnetic wave, is suffering from the scarcity of the efficient devices and might take the advantage of metamaterials. Here, we demonstrate design, fabrication, and characterization of a terahertz absorber based on a simple fishnet metallic film separated from a ground mirror plane by a dielectric spacer. Such absorbers are in particular important for bolometric terahertz detectors, high sensitivity imaging, and terahertz anechoic chambers. Recently, split-ring-resonators (SRR) have been employed for metamaterial-based absorbers at microwave and THz frequencies. The experimental demonstration reveals that such absorbers have absorptivity close to unitymore » at resonance frequencies. However, the downside of these designs is that they all employ resonators of rather complicated shape with many fine parts and so they are not easy to fabricate and are sensitive to distortions.« less
Authors:
 [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [1]
  1. Los Alamos National Laboratory
Publication Date:
OSTI Identifier:
979674
Report Number(s):
LA-UR-09-07901; LA-UR-09-7901
TRN: US201011%%371
DOE Contract Number:
AC52-06NA25396
Resource Type:
Conference
Resource Relation:
Conference: Conference on Lasers and Electro Optics ; May 16, 2010 ; San Jose, CA
Research Org:
Los Alamos National Laboratory (LANL)
Sponsoring Org:
DOE
Country of Publication:
United States
Language:
English
Subject:
42; ABSORPTION; ABSORPTIVITY; COMPOSITE MATERIALS; DESIGN; DIELECTRIC MATERIALS; ELECTROMAGNETIC RADIATION; FABRICATION; LASERS; MIRRORS; OPTICS; PERMEABILITY; PERMITTIVITY; POLARIZATION; REFLECTION; RESONANCE; RESONATORS; SENSITIVITY; SHAPE; SYMMETRY