Related papers: Semiclassical approach to the line shape
We study resonant two-photon ionization of helium atoms via the $1s3p$, $1s4p$ and $1s5p^1$P$_1$ states using the 15$^\mathrm{th}$ harmonic of a titanium-sapphire laser for the excitation and a weak fraction of the laser field for the…
We investigate a nonlinear response of the physical vacuum by the example of the third harmonic in radiation of the electron-positron-photon plasma excited by a strong time dependent electric field at the focus spot of counterpropagating…
Recent proposals suggest that lasers based on narrow dipole-forbidden transitions in cold alkaline earth atoms could achieve linewidths that are orders of magnitude smaller than linewidths of any existing lasers. Here, we demonstrate a…
We investigate the angle-resolved photoelectron spectra from laser-assisted photoionization for helium and neon atoms using an \textit{ab initio} method based on time-dependent surface flux and configuration interaction singles. We find…
Within the scope of the relativistic quantum theory for electron-laser interaction in a medium and using the resonant approximation for the two degenerated states of an electron in a monochromatic radiation field [1] a nonperturbative…
Our analysis of the experimental data related to nonphotochemical laser induced nucleation in solutions leads to the inevitable conclusion that the phase transformation is initiated by particles that are metallic in nature. This conclusion…
We propose the application of laser cooling to a number of transition-metal atoms, allowing numerous bosonic and fermionic atomic gases to be cooled to ultra-low temperatures. The non-zero electron orbital angular momentum of these atoms…
We extend the semiclassical two-step model [Phys. Rev. A 94, 013415 (2016)] to include a multielectron polarization-induced dipole potential. Using this model we investigate the imprints of multielectron effects in the momentum…
The motion of metastable helium atoms travelling through a standing light wave is investigated with a semi-classical numerical model. The results of a calculation including the velocity dependence of the dipole force are compared with those…
We present a combined numerical and theoretical study of atomic photoionization in the time domain. We show how a photoelectron wave packet rapidly changes its shape after being emitted, from a complex multi-peak structure to eventually a…
Interaction of a strong laser pulse with matter transfers not only energy but also linear momentum of the photons. Recent experimental advances have made it possible to detect the small amount of linear momentum delivered to the…
We show that QED nonlinear effects imply a phase correction to the linear evolution of electromagnetic waves in vacuum. We provide explicit solutions of the modified Maxwell's equations for the propagation of a superposition of two plane…
Collinear laser spectroscopy experiments on fast, neutral beams have been extensively used for studies on short-lived radioactive nuclei, taking advantage of its high sensitivity. The resulting resonance line-shape is known to show…
We present a comprehensive study of the electronic transitions in neutral cadmium (Cd I) with a focus on forbidden transitions, motivated by recent advances in laser technology and the growing relevance of cadmium in quantum gas research,…
A new method is proposed to produce population inversion on transitions involving the ground state of atoms. The method is realized experimentally with sodium atoms. Lasing at the frequency corresponding to the sodium D_2 line is achieved…
Coherent control of interfering one- and two-photon processes has for decades been the subject of research to achieve the redirection of photocurrent. The present study develops two-pathway coherent control of ground state helium atom…
Laser-induced optical potentials for atoms have led to remarkable advances in precision measurement, quantum information, and towards addressing fundamental questions in condensed matter physics. Here, we describe analogous optical…
We present a theoretical analysis of nearly monochromatic light propagation through a gas of two-level atoms using the Heisenberg-Langevin equation method. Our focus is on the evolution of the photon annihilation operator and its impact on…
The process of electron-positron pair creation through multi-photon absorption in a space-time dependent electric field is analyzed using computational quantum field theory. Our findings reveal two distinct pair creation channels: the…
We study the process of energy conversion from overcritical electric field into electron-positron-photon plasma. We solve numerically Vlasov-Boltzmann equations for pairs and photons assuming the system to be homogeneous and anisotropic.…