Related papers: Photoionization of atoms stuffed inside a two-shel…
Quantum coherence plays a fundamental role in the study and control of ultrafast dynamics in matter. In the case of photoionization, entanglement of the photoelectron with the ion is a well known source of decoherence when only one of the…
We apply time-dependent R-matrix theory to study inner-shell ionization of C atoms in ultra-short high-frequency light fields with a photon energy between 170 and 245 eV. At an intensity of 10$^{17}$ W/cm$^2$, ionization is dominated by…
We analyze the role of shake-off and of the final state interactions in inelastic processes in the fullerene shell which follow ionization of the caged atom. We demonstrate that in the broad interval of the photon energies the process is…
Coherence among rotational ion channels during photoionization is exploited to control the anisotropy of the resulting photoelectron angular distributions at specific photoelectron energies. The strategy refers to a robust and single…
The analytical structure and absolute values of the generalized cross-section of the two-photon resonance single ionization of the K-shell of a heavy neon-like ion of an iron atom (Fe$^{16+}$) were theoretically predicted. A pronounced…
Attention: this version-$2$ of the manuscript differs from its previously uploaded version-$1$ (arXiv:1112.6158v1) and subsequently published in 2012 J. Phys. B \textbf{45} 105102 only by a removed typo in Eq.(2) of version-$1$; there was…
The two-photon annihilation of a positron with an electron bound in the 1s state of a H-like ion is calculated within the fully relativistic QED framework. The interaction with the nucleus is treated nonperturbatively, thus allowing the…
The two-photon decay in hydrogen-like ions is investigated within the framework of second order perturbation theory and Dirac's relativistic equation. Special attention is paid to the angular correlation of the emitted photons as well as to…
We demonstrate that the angular distribution of electrons knocked out from an atom by a fast charge particle is determined not only by dipole but also by quadrupole transitions, the contribution of which can be considerably enhanced as…
We present a theoretical study on polarization-averaged molecular-frame photoelectron angular distributions (PA-MFPADs) emitted from $1s$ orbital of oxygen atom of dissociating dicationic carbon monoxide CO$^{2+}$. Due to the…
We consider the process of double photoionization (DPI) in a rare gas atom as a two-step process, namely (i) photoionization in an inner shell followed by (ii) the emission of an Auger electron from an outer shell. An angular correlation…
Photoionization of an atom $A$, in the presence of a neighboring atom $B$, can proceed via resonant excitation of $B$ with subsequent energy transfer to $A$ through two-center electron-electron correlation. We demonstrate that this…
A deeper insight into electron elastic scattering off endohedral fullerenes $A$@C$_{60}$ is provided. The study accounts for polarization of both the encapsulated atom $A$ and C$_{60}$ cage by an incident electron. It is carried out in the…
Resonant two-photon ionization in a system consisting of two spatially well-separated atoms is studied. Due to two-center electron-electron correlations, the ionization may also proceed through photo-excitation of both atoms with subsequent…
Within the framework of the second-order non-relativistic quantum perturbation theory, the methods of the theory of irreducible tensor operators, and nonorthogonal orbitals, the absolute values and shape of the generalized cross-sections of…
Exchange correlation plays an important role in double-ionization of complex atoms by ultrashort laser pulse. In this work, we investigate two-photon double inner-shell electron ionization of neon induced by an attosecond extreme…
A one parameter expression for the single ionization cross-section of atoms by electron impact is presented. Using this expression, the agreement obtained with available experimental data for 45 elements (from ionization threshold up to 200…
We theoretically study the photoelectron angular distributions (PADs) from two-color two-photon near-threshold ionization of hydrogen and noble gas (He, Ne, and Ar) atoms by a combined action of femtosecond extreme ultraviolet (EUV) and…
We report a theoretical investigation of photoionization by a pair of coherent, ultrashort fundamental and second-harmonic extreme-ultraviolet pulses, where the photon energies are selected to yield the same photoelectron energy for…
It is demonstrated that in photoabsorption by endohedral atoms some atomic Giant resonances are almost completely destroyed while the others are totally preserved due to different action on it of the fullerenes shell. As the first example…