Probing the electronic trigonal warping effect in individual single-wall carbon nanotubes using phonon spectra
نویسندگان
چکیده
We have studied the trigonal warping effect in metallic carbon nanotubes using resonance Raman scattering and examining the G0-band profile for individual metallic single-wall carbon nanotubes. We show that the observed splitting in the G0-band phonon spectra is directly correlated with the splitting in the singularities of the joint density of electronic states, i.e., detailed information about the 1D electronic structure is extracted from a phonon measurement. By correlating the phonon data with the calculated electronic structure for several ðn;mÞ nanotubes, we were able to determine the G0-band dispersion 1⁄2ðoxG0=oElaserÞ 1⁄4 108 6 cm =eV by using a single laser energy. 2002 Published by Elsevier Science B.V.
منابع مشابه
Ab Initio Study of Chirality Effects Onphonon Spectra, Mechanical and Thermal Properties of Nearly Samediameter Single Wall Carbon Nanotubes
In this paper, we have used density functional perturbation theory (DFPT) and Pseudo-potential method to calculate the phonon spectrum, phonon density of states (DOS), specific heat capacity and mechanical properties of (5,5) armchair and (9,0) zigzag Single Wall Carbon Nanotubes (SWCNTs). Our calculations show that Young’s modulusfor (5,5) and (9,0) nanotubesare higher than 1TPa. We have also ...
متن کاملQuantized phonon spectrum of single-wall carbon nanotubes
The electronic spectra of carbon nanotubes and other nanoscale systems are quantized because of their small radii. Similar quantization in the phonon spectra has been difficult to observe because of the far smaller energy scale. We probed this regime by measuring the temperature-dependent specific heat of purified single-wall nanotubes. The data show direct evidence of one-dimensional quantized...
متن کاملResonance Raman Spectroscopy of Single-Walled Carbon Nanotubes
The unusual one-dimensional properties of phonons in crystalline arrays of carbon nanotubes is presented. The main technique for probing the phonon spectra is Raman spectroscopy and the many unique and unusual features of the Raman spectra of carbon nanotubes are highlighted. Various features of the first-order Raman spectra are emphasized, with regard to their 1D behavior and special character...
متن کاملTrigonal warping effect of carbon nanotubes
Chirality-dependent van Hove singularities ~vHs! of the one-dimensional electronic density of states ~DOS! are discussed in connection with resonant Raman spectroscopy. The effect of trigonal warping on the energy dispersion relations near the Fermi energy splits the peaks of the density of states for metallic nanotubes, and the magnitude of this effect depends on the chiral angle of the carbon...
متن کاملPhotoconductivity spectra of single-carbon nanotubes: implications on the nature of their excited States.
We have measured the photoconductivity excitation spectra of individual semiconducting carbon nanotubes incorporated as the channel of field-effect transistors. In addition to the pronounced resonance that correlates with the second van Hove transition (E(22)) in semiconducting carbon nanotubes, a weaker sideband at about 200 meV higher energy is observed. Electronic structure calculations that...
متن کامل