Optical reflectance of patterned frost column-like CNT forest for metamaterial applications
Abstract
In this paper, the optical properties of a frost column-like carbon nanotube (CNT) forest, a hybrid structure of carbon film and a CNT forest, in which carbon films are supported by low-density, vertically-aligned CNT forests, are reported for the first time. The frost column-like CNT forest exhibits a significant interference reflectance, which is not typically observed in conventional CNT forests. Oscillating spectra in the visible (VIS) reflectance were analyzed by simple optical interference between the substrate and carbon films. Fishnet type metamaterial patterns of catalyst films were successfully fabricated by focused ion beam (FIB) pattern processing, followed by CNT growth using a thermal catalytic chemical vapor deposition (CVD) method. Optical properties of fishnet-type frost column-like CNT forest were also investigated. We also found that within the infrared region, optical absorption increased with fishnet type metamaterial CNT, frost column-like CNT forest, compared with non-patterned one. These results suggested that a metamaterial effect of fishnet patterns was observed.
- Publication:
-
Diamond and Related Materials
- Pub Date:
- March 2018
- DOI:
- 10.1016/j.diamond.2018.02.004
- Bibcode:
- 2018DRM....83..196M
- Keywords:
-
- Carbon nanotubes;
- Optical reflectance;
- Frost column-like CNT forest;
- Metamaterial;
- Fishnet