Raman and Transport Studies in Multi-Walled Carbon Nanotubes

Abstract

We report the characterization of electrical properties for multi-walled carbon nanotubes (MWNTs) synthesized by the arc-discharge method, as to the difference of characteristics between two diameters of 10 nm and 100 nm. In a result of Raman spectrums, we have observed clear radial-breathing-mode peak at approximately 255 cm−1, which corresponds in turn to an innermost diameter of ∼2 nm in the MWNT, and shows a good agreement with the TEM image of diameter of the thin MWNT. The results of two- and fourterminal measurements of the thin MWNTs show a power-law behavior as expected for the Tomonaga-Luttinger liquid model. The power-law exponent, α ∼ 0.4, seems consistent with the one-dimensional nature of the transport in these structures. We have also investigated the thick MWNTs.