相关论文: Over-the-barrier electron detachment in the hydrog…
A simple analytical solution for the problem of multiphoton detachment from negative ions by a linearly polarized laser field is found. It is valid in the wide range of intensities and frequencies of the field, from the perturbation theory…
Photodetachment of the outer-most electrons in few- and many-electron atomic systems is studied in the non-relativistic dipole approximation. Such a photodetachment is analyzed for the neutral atoms and positively charged atomic ions. We…
Nonrelativistic over-barrier ionization (OBI) of atoms in strong electric fields is studied, focussing on hydrogen and helium as concrete examples. Our goal is, on the one hand, to develop an intuitive physical picture behind established…
We consider double ionization of atoms or ions by electron impact in the presence of a static electric field. As in Wanniers analysis of the analogous situation without external field the dynamics near threshold is dominated by a saddle.…
A detailed study of the lowest states $1s_0, 2p_{-1}, 2p_0$ of the hydrogen atom placed in a magnetic field $B\in(0-4.414\times 10^{13} {\rm G})$ and their electromagnetic transitions ($1s_{0} \leftrightarrow 2p_{-1}$ and $ 1s_{0}…
Absolute two-photon detachment cross sections and photoelectron angular distribution are calculated for halogen negative ions within lowest-order perturbation theory. The Dyson equation method is used to obtain the outer np ground-state…
Absorption of infrared and visible radiation from stellar emission spectra by the negatively charged hydrogen ions H$^{-}$ is considered. The explicit formula for the photodetachment cross-section of the negatively charged hydrogen ion(s)…
The description of threshold fragmentation under long range repulsive forces is presented. The dominant energy dependence near threshold is isolated by decomposing the cross section into a product of a back ground part and a barrier…
Studies of atomic systems in electric fields are challenging because of the diverging perturbation series. However, physically meaningful Stark shifts and ionization rates can be found by analytical continuation of the series using…
A theory of electron detachment from atoms or negative ions by a superposition of a static and a laser (or, more generally, ac) fields, parallel to each other, is developed in the case when the photon energy and the field amplitude are much…
Quasi-static models of barrier suppression have played a major role in our understanding of the ionization of atoms and molecules in strong laser fields. Despite their success, in the case of diatomic molecules these studies have so far…
Tunneling and over-barrier ionization are the primary processes of strong-field ionization of atoms and molecules. While the dynamics of tunneling ionization have been extensively studied, exploration of over-barrier ionization dynamics has…
Thomas-Fermi model is applied to describe some basic properties of a negative hydrogen ion in a strong electric field. The equilibrium ionic size, energy and polarizability of the ion are calculated. Collective modes of the dipole…
We develop an Over Barrier Model for computing charge exchange between ions and one-active-electron atoms at low impact energies. The main feature of the model is the treatment of the barrier crossing process by the electron within a…
Negative ion detachment in bichromatic laser field is considered within the adiabatic theory. The latter represents a recent modification of the famous Keldysh model for multiphoton ionization which makes it quantitatively reliable. We…
For the hydrogen atom in combined magnetic and electric fields we investigate the dependence of the quantum spectra, classical dynamics, and statistical distributions of energy levels on the mutual orientation of the two external fields.…
The lowest bound states of the hydrogen negative ion and negative donor systems in a homogeneous magnetic field are investigated theoretically via a full configuration interaction approach with an anisotropic Gaussian basis set. The broad…
In this paper we study the ionization rate and the Stark shift of a one-dimensional model of the H$_{2}^{+}$ ion. The finding of these two quantities is reduced to the solutions of a complex eigenvalue problem. We solve this problem both…
The motion of electrons under homogeneously applied electric fields in low-dimensional systems with non-zero off-diagonal effective mass (ODEM) is studied. The equation describing the time evolution of a probability coefficient of finding…
In the combination of crossed electric and magnetic fields and the Coulomb field of the atomic nucleus the spectrum of the Rydberg electron in the vicinity of the Stark saddle-point are investigated at a quantum mechanical level. The…