V. A. Aleksandrov

Scattering of a particle at a crystal-structure atom

The interaction between an atom located inside a crystal structure and a moving external particle is accompanied by changes in its environment, and as a consequence, the atom is additionally affected by it. The force impact of the image of a moving multiply charged ion on the state of an ultrathin carbon film is calculated. The p possibility of forming a pore in the film as a result of ion propagation through the film is shown. The size of the pore turns out to be strictly correlated with that of the ion wave packet incident from free space on the thin-film carbon crystal structure. It is possible to trace the formation of the boundary with a classically inaccessible region called the caustic surface by numerically solving the three-dimensional nonstationary Schrödinger equation in the problem of the collision between a moving multiply charged ion and a carbon atom. On the whole, the performed calculation confirms the previously obtained results.

Study of the influence of vacancies and atoms adsorbed into carbon nanotube walls on ion dechanneling using a computer simulation

Specific features of the channeling of ions and atomic particles in carbon nanotubes in the presence of vacancies on the tube walls and adsorbed atoms inside it are studied by means of computer simulation. The channeling parameters sensitive to the concentrations of vacancies and adsorbed atoms and their localizations are determined for the use of atomic beams in probing nanotubes.

Atomic particle channeling simulation in carbon nanotubes

The ion distributions of vibration and rotation energies, as well as of the degree of torsion at the nanotube outlet, have been calculated via mathematical simulation of molecular hydrogen ion channeling in a carbon nanotube. The observed resonance effects have been analyzed. It is found that the probability of ion detection increases near the axis of a chiral carbon nanotube.

Calculating the probability of pore formation by multicharged ions incident on an ultrathin film

The problem of pore formation during the propagation of Xe+q ions with energies of around 50 keV and charges q = 20–54 through an ultrathin carbon film is discussed. The results from calculations suggest that pore formation can be attributed to the perforation of part of a bombarded film by the moving wave packet of a xenon ion with a sufficiently high charge.

Study of the rearrangement of a hydrogen atom moving parallel to the carbon nanotube wall

The processes that occur in a hydrogen atom during its movement with a certain velocity along the atomic row of a carbon nanotube have been considered. The change in the atomic state has been calculated using a numerical solution to the nonstationary Schrödinger equation. The atom ionization time has been estimated.

Nonregular phenomena in systems of quantum wells in the presence of tunneling processes

The effect of tunneling on inelastic processes in atomic collision physics has been studied using two examples: head-on collision between hydrogen atoms and protons and hydrogen-atom reflection from an impenetrable wall. These phenomena are analyzed using the numerical solution of the nonstationary Schrödinger equation.

Generation of surface plasmons in a conductor by moving charges

The surface polarization fields generated by a charge moving near a sphere or cylinder have been considered. This problem is related to the phenomena arising in an arc discharge in a gas near a solid surface during the formation of conducting cylindrical or spherical nanostructures, in particular, carbon nanotubes or fullerenes. The polarization fields, forces, energy losses, and other characteristics have been calculated.

Penetration of Waves and Particles through Porous Structures

The penetration of quantum and classical charged particles through porous films is investigated. The passage of quantum particles is analyzed by numerically solving the Schrödinger equation. The force of polarization acting on a charge is calculated by means of classical electrodynamics. The possibility of perforating thin films is analyzed.

Role of vacancies and adsorbed atoms in the channeling of molecular particles in CNTs

The channeling of atomic and molecular particles in carbon nanotubes is considered in the presence of vacancies on the walls and of adsorbed atoms inside them. It is shown that the significant influence of the indicated disturbance of nanotube structures greatly affects channeling, which makes it possible to use beams of atomic and molecular particles to probe nanotubes.

Study of the peculiarities of atomic particle channeling in nanotube bundles by means of computer simulation

The channeling of hydrogen atoms in bundles of carbon nanotubes in the presence of vacancies on walls and adsorbed atoms inside the tubes is studied by means of computer simulation. A change in the parameters of the beam of channeling particles during interaction with the indicated defects makes it possible to detect the structural damage of nanotube bundles.