We study the properties of flat bands that appear in a heterostructure composed strands different widths graphene armchair nanoribbons. One is reminiscent one appears pristine nanoribbons and has its origin quantum mechanical destructive interference effect, dubbed ``Wannier orbital states'' by Lin et al. Phys. Rev. B 79, 035405 (2009). The additional found these heterostructures, some reasonab...

Submitted for the MAR10 Meeting of The American Physical Society A hybrid density functional study of double walled armchair SiC nanotubes1 KAPIL ADHIKARI, ASOK RAY, Department of Physics, University of Texas Arlington — As a continuation of our studies of single walled SiC nanotubes,2 we report here a systematic study of double walled armchair type1 SiC nanotubes using the finite cluster appro...

Graphene nanoribbons (GNRs)-narrow stripes of graphene-have emerged as promising building blocks for nanoelectronic devices. Recent advances in bottom-up synthesis have allowed production of atomically well-defined armchair GNRs with different widths and doping. While all experimentally studied GNRs have exhibited wide bandgaps, theory predicts that every third armchair GNR (widths of N=3m+2, w...

We study the effect of twist on the electronic structure of H-terminated armchair graphene nanoribbons, for both relaxed and unrelaxed unit cell size. We investigate the band gap change as a function of the twist angle for different ribbon widths. In the case of unrelaxed unit cell size, the band gap closes for smaller twist angles as opposed to relaxed unit cell size. We calculate strain energ...

We solve the Green's equation exactly for the armchair-type carbon nanotubes with the one-electron tight-binding Hamiltonian and obtain analytic expressions for the conductance of the nanotube with local perturbations. Our results explicitly show the dependence of the conductance on the Fermi level, the tubular radius, and the strength of the perturbation. A carbon nanotube is a new form of gra...

In this paper we demonstrate that soliton solutions, whose existence is well known in one-dimensional (1D) model anharmonic systems, can also exist in more complex systems such as carbon nanotubes (CNT). We investigate armchair and zigzag nanotubes and show that both can be simplified to anharmonic 1D lattice models with reduced internal degrees of freedom. Because of the differences in chirali...

Abstract. We study quantum transport in honeycomb lattice ribbons with either armchair or zigzag edges. The ribbons are coupled to semi-infinite linear chains serving as the input and output leads and we use a tight-binding Hamiltonian with nearest-neighbor hops. For narrow ribbons we find transmission gaps for both types of edges. The center of the gap is at the middle of the band in ribbons w...