Electron transfer and ionization in collisions of lowly charged ions with atoms and molecules.

Abstract

We have been mostly concerned with the electron transfer and related processes that occur in heavy body collisions, particularly in lowly charged ion-atom and ion-diatomic collisions. First, we have studied the O+/H_2 collision system, namely calculated the first state resolved cross sections of electron target and projectile excitations, and electron capture for the O+(4S), O+*(2D) and O+*(2P) ions. Next, we have studied ionization of hydrogen by proton impact for keV collision energies and obtained differential and total ionization cross sections by molecular orbital close coupling with the electron transfer factor (ETF) corrections, based on the explicit calculation of bound-continuum couplings. Selection of the collision partners, which are the partially of fully ionized primary plasma constituents (p, H, also He+) ties closely with the applications in fusion experiments. Finally, we have studied the electron transfer in multi-layer quantum dot (QD) devices, namely the rates of tunnelling escape from separated dots as a function of QD charge and geometry.Our results show that tunnelling may substitutionally contribute to electric current in recently improved QDs, which has low confinement potentials and accommodate small number of electrons. Currently, we have extended the present model in order to study electron interactions in concentric disk quantum dots.Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi