Dielectric properties of vertically aligned multi-walled carbon nanotubes in the terahertz and mid-infrared range

0489481 - FZÚ 2019 RIV GB eng J - Journal Article
Thomson, M.D. - Zouaghi, W. - Meng, F. - Wiecha, M.M. - Rabia, K. - Heinlein, T. - Hussein, L. - Babu, D. - Yadav, S. - Engstler, J. - Schneider, J.J. - Nicoloso, N. - Rychetský, Ivan - Kužel, Petr - Roskos, H.G.
Dielectric properties of vertically aligned multi-walled carbon nanotubes in the terahertz and mid-infrared range.
Journal of Physics D-Applied Physics. Roč. 51, č. 3 (2018), s. 1-7, č. článku 034004. ISSN 0022-3727. E-ISSN 1361-6463
R&D Projects: GA ČR GA17-03662S
Institutional support: RVO:68378271
Keywords : carbon nanotubes * terahertz spectroscopy * effective medium theory
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 2.829, year: 2018

We investigate the broadband dielectric properties of vertically aligned, multi-wall carbon nanotubes (VACNT), over both the terahertz (THz) and mid-infrared spectral ranges. A detailed comparison of various conductivity models and previously reported results is presented for the non-Drude behaviour we observe in the conventional THz range (up to 2.5 THz). Extension to the mid-infrared range reveals an absorption peak at 24 THz. To account for the observed resonance here, we apply a Bergman-type effective-medium theory including both the intra- and inter-tube response, which can reproduce the observed spectrum if one assumes a much higher plasma frequency and scattering rate than that reflected in the low-frequency spectra, and proposes an explanation for the non-Drude behaviour at low-frequencies.

Permanent Link: http://hdl.handle.net/11104/0283890