Experiments recently showed that the finite lengths of single-wall carbon nanotubes (SWNTs) randomly dispersed and randomly aligned in a composite material are responsible for the appearance of a broad peak in its terahertz conductivity. We investigated, both theoretically and experimentally, the influences of the cross-sectional diameter and the acid-induced p-type doping of SWNT bundles in composite materials on their terahertz conductivity peaks (TCPs). We found that the TCP blue-shifts if the inclusion diameter is larger, and that doping enhances the effective conductivity of the composite material. But, a theoretical prediction of the blue-shifting of the TCP by p-type doping was only weakly supported by experimental evidence. All experimental observations turned out to be in good qualitative agreement with the concept of localized plasmon resonance in SWNTs.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics