Related papers: Chemically active substitutional nitrogen impurity…
In weakly buckled carbon nanotubes, the kink is an open, ovalized constriction where molecular-sized analytes and ions can pass. Moreover, in semiconducting tubes, the kink has an electronic bound state within the bandgap. This state is…
The properties of single-walled carbon nanotubes (SWCNTs) and graphene can be modified by the presence of covalently bound impurities. Although this can be achieved by introducing chemical additives during synthesis, that often hinders…
The electronic structures of zig-zag and arm-chair single-walled carbon nanotubes interacting with a transitional-metal atomic nanowire of Ni have been determined. The Ni nanowire creates a large electron density of states (DOS)at the Fermi…
Density functional methods have been used to calculate the electronic properties of aligned smalldiameter single-walled carbon nanotubes under hydrostatic pressures. Abrupt pressure induced semiconductor-metal and metal-semiconductor…
We show that quantum confinement in the valence and conduction bands of semiconducting single-walled carbon nanotubes can be engineered by means of artificial defects. This ability holds potential for designing future nanotube-based quantum…
Low-temperature electronic conductance in nanocontacts, scanning tunneling microscopy (STM), and metal break junctions involving magnetic atoms or molecules is a growing area with important unsolved theoretical problems. While the detailed…
We present a detailed comparison between theoretical predictions on electron scattering processes in metallic single-walled carbon nanotubes with defects and experimental data obtained by scanning tunneling spectroscopy of Ar$^+$ irradiated…
We investigate a disordered single-walled carbon nanotube (SWCNT) in an effective medium super cell approximation (EMSCA). First type of disorder that we consider is the presence of vacancies. Our results show that the vacancies induce some…
We show that the electronic and atomic structure of carbon nanotubes undergo dramatic changes with hydrogen chemisorption from first principle calculations. Upon uniform exohydrogenation at half coverage, the cross sections of zigzag…
We present a first-principle study of geometrical and electronic structure of hexagonal single-walled silicon nanotubes with a monovacancy or a substitutional defect. The C, Al or P atoms are chosen as substitutional impurities. It is found…
We investigate the coupling between individual tubes in a rope of single-wall carbon nanotubes using four probe resistance measurements. By introducing defects through the controlled sputtering of the rope we generate a strong non-monotonic…
We have theoretically investigated thermoelectric (TE) effects of narrow-gap single-walled carbon nanotubes (SWCNTs) with randomly substituted nitrogen (N) impurities, i.e., N-substituted (20,0) SWCNTs with a band gap of 0.497 eV. For such…
We consider electronic spectra of graphene nanotubes and their perturbation by impurity atoms absorbed at different positions on nanotube surfaces, within the framework of Anderson hybrid model. A special attention is given to the cases…
A comprehensive first-principles theoretical study of the electronic properties and half-metallic nature of finite zigzag carbon nanotubes is presented. Unlike previous reports, we find that all nanotubes studied present a spin-polarized…
We have combined large-scale, $\Gamma$-point electronic-structure calculations with the maximally-localized Wannier functions approach to calculate efficiently the band structure and the quantum conductance of complex systems containing…
The stability and properties of the monovacancy and the divacancy in single-walled carbon nanotubes (CNTs) are addressed by spin-density functional calculations. We study these defects in four nanotubes, the armchair (6,6) and (8,8) and the…
We investigate the properties of conduction electrons in single-walled armchair carbon nanotubes in the presence of mutually orthogonal electric and magnetic fields transverse to the tube's axis. We find that the fields give rise to an…
Low-temperature thermal conductivity and thermopower of multiwalled carbon nanotubes considered within a bundle of nanotubes are calculated taking into account multiple scattering of electrons on the atoms of impurities (like single carbon…
Carbon nanotubes are one-dimensional and very narrow. These obvious facts imply that under doping with boron and nitrogen, microscopic doping inhomogeneity is much more important than for bulk semiconductors. We consider the possibility of…
We report wide-range optical investigations on transparent conducting networks made from separated (semiconducting, metallic) and reference (mixed) single-walled carbon nanotubes, complemented by transport measurements. Comparing the…