We consider the Schrödinger operator on the zigzag and armchair nanotubes (tightbinding models) in a uniform magnetic field B and in an external periodic electric potential. The magnetic and electric fields are parallel to the axis of the nanotube. We show that this operator is unitarily equivalent to the finite orthogonal sum of Jacobi operators. We describe all spectral bands and all eigenval...

Graphene antidot lattices constitute a novel class of nano-engineered graphene devices with controllable electronic and optical properties. An antidot lattice consists of a periodic array of holes that causes a band gap to open up around the Fermi level, turning graphene from a semimetal into a semiconductor. We calculate the electronic band structure of graphene antidot lattices using three nu...

We outline the main ideas underlying the CONQUEST code for first-principles modelling of systems containing many thousands of atoms, focusing on the algorithms used to achieve linear-scaling of the cpu and memory requirements with number of atoms, and the strategies for implementing the algorithms so as to achieve good parallel scaling on parallel computers. We note that the code can be run at ...

In this first of three articles on the optical absorption of electrons in half-filled Peierls-distorted chains we present analytical results for non-interacting tightbinding electrons. We carefully derive explicit expressions for the current operator, the dipole transition matrix elements, and the optical absorption for electrons with a cosine dispersion relation of band width W and dimerizatio...

Inhibition of HIV-1 protease (HIV-PR), the aspartic protease that cleaves specific amide bonds in precursor gag-pol proteins to form the mature proteins needed for production of infectious human immunodeficiency virus (HIV) particles,' is regarded as a promising approach for treating acquired immunodeficiency syndrome (AIDS) and related diseases. Tight-binding inhibitors of HIV-PR have been dis...

Two dimensional van der Waals heterostructures have shown promise in electronic device applications because of their high charge carrier mobility, large surface area and large spin conductance value. However, it still remains a great challenge to design heterolayers with an electric field driven tunable electronic bandgap and stable geometry to obtain high electron mobility. Motivated by the in...

The coalescent properties of ZnO clusters were studied through experiment and molecular dynamics simulation in combination with the tightbinding potential and ZnO potential. The results from the simulation show that the linearly relationship between the melting temperature and the function of atom numbers of N was obtainable. Extrapolating the result yield at a melting point of 2130 K for N/N (...

Carbon nanotubes (CNTs) have been attracting attention because of their characteristic mechanical and electronic properties. It has been pointed out that a single-walled CNT can stretch in the axial direction at 30% strain without any bonds breaking. Therefore, it is of interest to investigate electronic properties of CNTs under high axial strain. In this study, we investigate the change in ele...

We investigate dynamical scaling properties of the one-dimensional tightbinding Anderson model with a weak diagonal disorder, by means of the spreading of a wave packet. In the absence of disorder, and more generally in the ballistic regime (t≪ ξ0 in reduced units, with ξ0 being the localisation length near the band centre), the wavefunction exhibits sharp fronts. These ballistic fronts yield a...

The effects of curvature on the structure, electronic and optical properties of isolated single-walled carbon nanotubes are studied within a symmetry-adapted non-orthogonal tight-binding model using 2s and 2p electrons of carbon. The symmetry-adapted scheme allows reducing the matrix eigenvalue problem for the electrons to diagonalization of 8 × 8 matrices for any nanotube type. Due to this sim...