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We perform ab initio calculations of charged graphene and single-wall carbon nanotubes (CNTs). A wealth of electromechanical behaviors is obtained: (1) Both nanotubes and graphene expand upon electron injection. (2) Upon hole injection, metallic nanotubes and graphene display a non-monotonic behavior: Upon increasing hole densities, the lattice constant initially contracts, reaches a minimum, and then starts to expand. The hole densities at minimum lattice constants are 0.3 |e|/atom for graphene and between 0.1 and 0.3 |e|/atom for the metallic nanotubes studied. (3)Semiconducting CNTs with small diameters (d <~ 20 A) always expand upon hole injection; (4) Semiconducting CNTs with large diameters (d >~ 20 A) display a behavior intermediate between those of metallic and large-gap CNTs. (5) The strain versus extra charge displays a linear plus power-law behavior, with characteristic exponents for graphene, metallic, and semiconducting CNTs. All these features are physically understood within a simple tight-binding total-energy model.
We calculate the electron-phonon scattering and binding in semiconducting carbon nanotubes, within a tight binding model. The mobility is derived using a multi-band Boltzmann treatment. At high fields, the dominant scattering is inter-band scattering
We use ab initio total-energy calculations to predict the existence of polarons in semiconducting carbon nanotubes (CNTs). We find that the CNTs band edge energies vary linearly and the elastic energy increases quadratically with both radial and with
We have applied the quantum Monte Carlo method and tight-binding modelling to calculate the binding energy of biexcitons in semiconductor carbon nanotubes for a wide range of diameters and chiralities. For typical nanotube diameters we find that biex
We present a detailed study of the vibrational properties of Single Wall Carbon Nanotubes (SWNTs). The phonon dispersions of SWNTs are strongly shaped by the effects of electron-phonon coupling. We analyze the separate contributions of curvature and
We study the low temperature phase behavior of hydrogen within a bundle of carbon nanotubes. Because the carbon environment weakens the attraction between molecules within the same interstitial channel (IC), the ground state of the one-dimensional (1