Hydrogen Atom In Electric Field Research Articles

Simple method for numerical solving of Schroedinger equation for hydrogen atom in electric field

A propagation numerical method for determining energy eigenvalues and eigen wave functions for hydrogen atom in constant and uniform electric field is described in this paper. Solution is presented for 3-D Schroedinger equation in natural parabolic co-ordinate system. Criteria for accepting eigenvalues are introduced, and results are compared with previous papers.

Dynamics of electron wave propagation in photoionization microscopy. II. Quantum-mechanical formulation

Complementary to the semiclassical method developed in the preceding paper, here we develop a quantum-mechanical approach to characterize propagation of electron waves to large distances in photoionization microscopy of hydrogen atoms in uniform external electric fields. A formula for outgoing electron waves from the atomic source produced in photoionization has been derived. Spatial distributions of electron probability densities can be determined using the obtained formula. The electron waves that propagate to a large distance due to photoionization from the $n=2$ initial state of hydrogen atoms in electric fields has been calculated and the resulting probability densities are presented. Comparison with semiclassical results is made, and they are found to be in good agreement. A detailed analysis is given of strong quantum tunneling effects found in our calculations.

Dynamics of electron wave propagation in photoionization microscopy. I. Semiclassical open-orbit theory

This is the first of two papers that develop theories and numerical methods for photoionization microscopy of hydrogen atoms in strong electric fields, in semiclassical and quantum-mechanical frameworks, respectively. In this paper, semiclassical open-orbit theory is presented to describe the propagation of outgoing electron waves to macroscopic distances. Spatial distributions of electron probability densities and current densities are predicted. The open-orbit theory, based on an assumption that electron waves propagate along classical paths from a pointlike source to a detector, provides a clear and intuitive physical picture to interpret structures of observed geometrical interference patterns in photoionization microscopy. We calculate photoelectron ejection of hydrogen atoms in electric fields, and comparison is made with quantum-mechanical results, which will be detailed in the second paper [Zhao and Delos, Phys. Rev. A 81, 053418 (2010)]. A strong quantum tunneling effect has been found. Such a tunneling effect should be visible in the experiment.

Semiclassical calculation of ionization rate for Rydberg hydrogen atoms near a metal surface

The ionization of Rydberg hydrogen atoms near a metal surface at different scaled energies above the classical saddle point energy has been discussed by using the semiclassical method. The results show that the atoms ionize by emitting a train of electron pulses. In order to reveal the chaotic and escape dynamical properties of this system in detail, the sensitive dependence of the ionization rate upon the scaled energy is discussed. As the scaled energy is close to the saddle point energy, the ionization process of the hydrogen atom is nearly the same as the case of hydrogen atom in an electric field. There is only a single pulse of electrons, with an exponentially decaying tail. With the increase of the scaled energy, the ionization rates are similar to the case of the hydrogen atom in parallel electric and magnetic field, a series of electron pulses appear in the ionization process. This is caused by classical chaos, which occurs for the metal surface. Our studies also suggest that the metal surface can play the role of both the electric and the magnetic fields. Our theoretical analysis will be useful for guiding experimental studies of the ionization of atoms near the metal surface.

Photoionization of atoms in parallel electric and magnetic fields: Cross-section calculations using the Lanczos algorithm and the complex coordinate method in a discrete variable representation

A combination of the complex-coordinate method and the Lanczos recursion scheme is implemented in the discrete variable representation (DVR) to obtain total photoionization cross-sections using an iterative procedure. Applications to photoionization of hydrogen atoms in electric fields and sodium atoms in electric and parallel electric and magnetic fields are presented and discussed.

L-mixing dynamics of Rydberg states of hydrogen atom in a static electric field

Both exact analytical formula and numerical calculations are performed to study the l-mixing population decay of the n = 10 and n = 100 high Rydberg states of hydrogen atoms in an electric field. The two time constants of and observed in zero-electron-kinetic-energy (ZEKE) experiments in the common stray field condition, i.e. - can be obtained by 2-exponential fitting of the exact decay curve. The principle of high-resolution ZEKE spctroscopy based on the two time constants is then elucidated. The inverse Born-Oppenheimer approximation will be introduced to treat the ZEKE states of complex systems like many-electron atoms, molecules, clusters etc.

Analytical estimation of the energies and widths of the Rydberg states of a hydrogen atom in an electric field

Abstract We have obtained analytical formulae permitting one to find with sufficiently high accuracy the positions and widths of highly excited states of the hydrogen atom in a homogeneous electric field. The functional dependence of these values on the quantum numbers of the system and on the field amplitude can be investigated by means of these formulae.

Nuclear magnetic shielding at large distances of a hydrogen atom in an electric field

The nuclear magnetic shielding constant of a hydrogen atom in a uniform electric field is calculated at a pointP which is situated at a large distance from the nucleus in the direction of the electric field. The main term of the screening constant is found to be proportional to the first power of the electric field and to the inverse second power of the distance betweenP and the hydrogen nucleus.

Nuclear magnetic shielding of a hydrogen atom in an electric field

The nuclear magnetic screening constant of a hydrogen atom in a uniform electric field is calculated, neglecting any effect of electron spin. The screening is found to be reduced by the electric field for all directions of the applied magnetic field, the reduction being greatest if the two fields are perpendicular.