Tunable nanostructured composite with built-in metallic wire-grid electrode

• Main Authors: Davide Micheli, Roberto Pastore, Gabriele Gradoni, Mario Marchetti
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2013-11-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/1.4837916

In this paper, the authors report an experimental demonstration of microwave reflection tuning in carbon nanostructure-based composites by means of an external voltage supplied to the material. DC bias voltages are imparted through a metal wire-grid. The magnitude of the reflection coefficient is measured upon oblique plane-wave incidence. Increasing the bias from 13 to 700 V results in a lowering of ∼20 dB, and a “blueshift” of ∼600 MHz of the material absorption resonance. Observed phenomena are ascribed to a change of the dielectric response of the carbon material. Inherently, the physical role of tunneling between nanofillers (carbon nanotubes) is discussed. Achievements aim at the realization of a tunable absorber. There are similar studies in literature that focus on tunable metamaterials operating at either optical or THz wavelengths.