Relativistic calculations of the non-resonant two-photon ionization of neutral atoms

Abstract

The non-resonant two-photon one-electron ionization of neutral atoms is studied theoretically in the framework of relativistic second-order perturbation theory and independent particle approximation. In particular, the importance of relativistic and screening effects in the total two-photon ionization cross section is investigated. Detailed computations have been carried out for the K-shell ionization of neutral Ne, Ge, Xe, and U atoms. The relativistic effects significantly decrease the total cross section, for the case of U, for example, they reduce the total cross section by a factor of two. Moreover, we have found that the account for the screening effects of the remaining electrons leads to occurrence of an unexpected minimum in the total cross section at the total photon energies equal to the ionization threshold, for the case of Ne, for example, the cross section drops there by a factor of three.

References in corpus (3)

• Enhanced nonlinear response of Ne${}^{8+}$ to intense ultrafast x rays
• Electron angular distributions in the two--photon ionization of hydrogen--like ions: relativistic description
• Angular distribution studies on the two-photon ionization of hydrogen-like ions: Relativistic description

Cited by in corpus (6)

• Photoelectron distribution of non-resonant two-photon ionization of neutral atoms
• Fluorescence polarization as a precise tool for understanding nonsequential many-photon ionization
• Breakdown of the electric dipole approximation at Cooper minima in direct two-photon ionisation
• Photoelectron Angular Distributions of Nonresonant Two-Photon Atomic Ionization Near Nonlinear Cooper Minima
• Polarization effects in the total rate of biharmonic $\omega +3\omega$ ionization of atoms
• Enhanced polarization transfer to the characteristic $L\alpha$ x-ray lines near the nonlinear Cooper minimum of two-photon ionization