Scientific Reports (Jun 2017)

Design and deposition of a metal-like and admittance-matching metamaterial as an ultra-thin perfect absorber

  • Yi-Jun Jen,
  • Wei-Chih Liu,
  • Tso-Kuei Chen,
  • Shan-wen Lin,
  • Yi-Ciang Jhang

DOI
https://doi.org/10.1038/s41598-017-03392-7
Journal volume & issue
Vol. 7, no. 1
pp. 1 – 10

Abstract

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Abstract A stratiform metamaterial, comprising metal and dielectric thin films, exhibits both near-perfect antireflection and strong light extinction to function as a perfect and ultra-thin light absorber. The equivalent admittance and extinction coefficient of the metamaterial are tailored using a visual method that is based on an admittance diagram. A five-layered metamaterial was designed and deposited with a total thickness of 260 nm on a mirror to exhibit strong and wide angle absorption over wavelengths from 400 nm to 2000 nm. A seven-layered metamaterial with a total thickness of less than 200 nm was designed and deposited to have equivalent admittance around unity and an extinction coefficient that is comparable to that of metal. Such a metal-like metamaterial exhibits low reflectivity so couples most visible light energy into the films and dissipates energy with an equivalent skin depth of less than 55 nm over visible wavelengths.