Complex optical index of single wall carbon nanotube films from the near-infrared to the terahertz spectral range

Abstract

We retrieve the complex optical index of single-walled carbon nanotube (CNT) films in the 0.6-800 μm spectral range. Results are obtained from a complete set of optical measurements, reflection and transmission, of free-standing CNT films using time domain spectroscopy in the terahertz (THz) and Fourier transform infrared (IR) spectroscopy in the visible-IR. Based on a Drude-Lorentz model, our results reveal a global metallic behavior of the films in the IR, and confirm their high optical index in the THz range.

Short-length carbon nanotubes as building blocks for high dielectric constant materials in the terahertz range

“…Our investigation includes fabrication, measurement and analysis of the terahertz effective permittivity of thin films comprising both long ( ⩾ µ L 0.5 m) and short ( ⩽ µ L 0.3 m) CNTs. Previously, the alternating-current conductivity and the effective permittivity of CNT films in the terahertz range have mainly only been studied experimentally [12][13][14][15][16][17]. The real part of the relative permittivity ( ) ε Re eff and the dielectric loss tangent…”

Carbon Nanotube Layer Modeling for Computer Simulation of Optically Controlled Phase Shifters

“…This term describes the plasmon resonance effect with the central frequency dependent on the finite length of the nanotubes [13], [14]. The Drude-Lorentz oscillator in this work was fitted to experimental measurements, with the initial values taken from [15] and [16]. The resulting parameters are summarized in Table 1, while a graphical representation of the complex dielectric constant in the 67-110 GHz frequency range is shown in Fig.…”

Self-imaging in multi-walled carbon nanotube arrays at visible wavelengths

“…We investigate self-imaging in multi-walled carbon nanotube arrays under TE polarized (transverse electric) illumination and ε ⊥ (ω) is considered by assuming curvature effects to be small enough. The dielectric function ε ⊥ (ω) for MWCNTs can be obtained through the widely used DrudeLorentz model [23][24][25][26], which can be expressed as…”