相关论文: Itinerant Flat-Band Magnetism in Hydrogenated Carb…
Motivated by the possibility of combining spintronics with molecular structures, we investigate the conditions for the appearance of spin-polarization in low-dimensional tubular systems by contacting them to a magnetic substrate. We derive…
A simple method to calculate the static electric polarization of single-walled carbon nanotube (SWNT) is obtained within the second-order perturbation approximation. The results are in agreement with the previous calculation within 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…
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…
The electronic properties of carbon nanotubes in a uniform transverse field are investigated within a single orbital tight-binding model. For doped nanotubes, the dielectric function is found to depend not only on symmetry of the tube, but…
We propose a method to modulate the bandgaps in quasi-metallic carbon nanotubes using a transverse electric field. Unlike previous investigations, we include curvature effects of the nanotubes by incorporating both $\pi$- and…
According to band theory, an ideal undoped (n,n) carbon nanotube is metallic. We show that the electron-electron interaction causes it to become Mott insulating with a spin gap. More interestingly, upon doping it develops superconducting…
An external magnetic field is found to have strong effects on the electronic structure of carbon nanotubes. A field-induced metal-insulator transition is predicted for all pure nanotubes. In a weak field, nanotubes exhibit both large…
We introduce two simple models to study the effect of a spatially localized transverse electric field on the low-energy electronic structure of semiconducting carbon nanotubes. Starting from the Dirac Hamiltonian for the low energy states…
We performed ab initio calculation on the pristine and carbon-doped (5,5) and (9,0) BN nanotubes. It was found that Carbon substitution for either boron or nitrogen in BN nanotubes can induce spontaneous magnetization. Calculations based on…
The measured electric resistance of carbon nanotubes wrapped with DNA molecules depends strongly on the spin of the injected electrons. Motivated by these experiments, we study the effect of helix-shaped potentials on the electronic…
We consider a semiconducting carbon nanotube (CNT) laying on a ferromagnetic insulating sub-strate with one end depassing the substrate and suspended over a metallic gate. We assume that the polarised substrate induces an exchange…
A mechanically bistable single-walled carbon nanotube can act as a variable-shaped capacitor with a voltage-controlled transition between collapsed and inflated states. This external control parameter provides a means to tune the system so…
Electron properties of Carbon nanotubes can change qualitatively in a transverse electric field. In metallic tubes the sign of Fermi velocity can be reversed in a sufficiently strong field, while in semiconducting tubes the effective mass…
By means of pseudopotential calculations based on density functional theory (DFT) we studied the effect of hydrogenation on electronic properties of armchair single-wall carbon nanotubes. The calculations demonstrate strong preference for…
We study, theoretically, the ground state spin of a carbon nanotube in the presence of an external potential. We find that when the external potential is applied to a part of the nanotube, its variation changes the single electron spectrum…
We study the effect of the Rashba spin-orbit interaction in the quantum transport of carbon nanotubes with arbitrary chiralities. For certain spin directions, we find a strong spin-polarized electrical current that depends on the diameter…
The electronic properties of carbon nanotubes are investigated in the presence of disorder and a magnetic field parallel or perpendicular to the nanotube axis. In the parallel field geometry, the $\phi_{0}(=hc/e)$-periodic metal-insulator…
Here we address a theoretical study on the behaviour of electronic states of heterojunctions and quantum dots based on carbon nanotubes under magnetic fields. Emphasis is put on the analysis of the local density of states, the conductance,…
We calculate the static longitudinal polarizability of single-wall carbon nanotubes in the long wavelength limit taking into account spin-orbit effects. We use a four-orbital orthogonal tight-binding formalism to describe the electronic…