Photodetachment cross section of S^- in electric and magnetic fields＊

In this paper, the quantum-mechanical photodetachment cross section of S^- in uniform electric and magnetic fields at arbitrary angles is presented. It compares the quantum-mechanical cross section with the quantum source formalism cross section. The results show that at large angle, the two results have good agreements, however, with the decrease of the angles, they deviate obviously from each other. The reasons for this discrepancy are also discussed.

Photodetachment of H^- in an electric field between two parallel interfaces

By using the closed orbit theory, the photodetachment cross section of H- in a static electric field between two parallel elastic interfaces is derived and calculated. It is found that the photodetachment cross section depends on the electric field and the distance between the ion and the elastic interface. The oscillation of the cross section becomes more complicated than in the case of H- near one elastic interface. The results show that near the detachment threshold, the influence of the additional interface can be neglected. But with the increase of the energy, its influence becomes great. At some energies, the cross sections display sharp peaks, contrasting with the staircase structure when only one interface exists. This study provides a new understanding of the photodetachment process of H- in the presence of external field and interfaces.

Quantum photodetachment of hydrogen negative ion in a harmonic potential subjected to static electric field

Photodetachment of negative ions has attracted immense interest owing to its fundamental nature and practical implications with regard to technology. In this study, we explore the quantum dynamics of the photodetachment cross section of negative ion of hydrogen H-in the perturbed one dimensional linear harmonic potential via static electric field. To this end,the quantum formula for total photodetachment cross section of the H-ion is derived by calculating the dipole matrix element in spherical coordinates. In order to obtain the detached electron wave function, we have solved the time-independent Schr¨odinger wave equation for the perturbed Hamiltonian of the harmonic oscillator in momentum representation. To acquire the corresponding normalized final state detached electron wave function in momentum space, we have employed an approach analogous to the WKB(Wenzel–Kramers–Brillouin) approximation. The resulting analytical formula of total photodetachment cross section depicts interesting oscillator structure that varies considerably with incident-photon energy,oscillator potential frequency, and electric field strength as elucidated by the numerical results. The current problem having close analogy with the Stark effect in charged harmonic oscillator may have potential implications in atomic and molecular physics and quantum optics.