相关论文: Electric-field induced helium-helium resonances
We investigate Collisionless Shock Acceleration of spin-polarized ${}^3$He for laser pulses with normalized vector potentials in the range $a_0 = 100-200$. The setup utilized in the 2D-PIC simulations consists of a solid Carbon foil that is…
Background: In recent years properties of light rare isotopes have been measured with high accuracy. At the same time, the theoretical description of light nuclei has made enormous progress, and properties of, e.g., the Helium isotopes can…
A mechanism of disappearance and formation of the Efimov levels of the helium ^4He trimer is studied when the force of the interatomic interaction is changed. It is shown that these levels arise from virtual levels which are in turn formed…
We study the electromagnetic responses of $^4$He within the framework of the self-consistent continuum random phase approximation theory. In this approach the ground state properties are described by a Hartree-Fock calculation. The single…
Several correlation and interference effects in strong-field physics are investigated. We show that the interference of continuum wave packets can be the dominant mechanism of high-harmonic generation (HHG) in the over-the-barrier regime.…
A setup for studying the influence of external electric fields on dynamic surface processes is described. Spatially-extended homogeneous electric fields are realized by applying a DC voltage in between a planar electrode and a metallic…
We have determined an atom-surface interaction potential for the He$-$Bi$_2$Te$_3$(111) system by analysing ultrahigh resolution measurements of selective adsorption resonances. The experimental measurements were obtained using $^3$He…
The resonant transfer of energy from the inversion sublevels in NH$_3$ to He atoms in triplet Rydberg states with principal quantum number $n=38$ has been controlled using electric fields below 15 V/cm in intrabeam collisions at…
We present a mathematically rigorous method for solving three-atomic bound state and scattering problems. The method is well suited for applications in systems where the inter-atomic interaction is of a hard-core nature. It has been…
Four-body distorted wave theory appropriate for nucleon-nucleus reactions leading to 3-body continuum excitations of two-neutron Borromean halo nuclei is developed. The peculiarities of the halo bound state and 3-body continuum are fully…
Electric dipole ($E1$) response of $^{6}$He is studied with a fully microscopic six-body calculation. The wave functions for the ground and excited states are expressed as a superposition of explicitly correlated Gaussians (CG). Final state…
We present a theoretical and experimental investigation of homonuclear ionizing collisions of laser-cooled metastable helium atoms, considering both the fermionic He-3 and bosonic He-4 isotope. The theoretical description combines quantum…
We report on the observation of phase space modulations in the correlated electron emission after strong field double ionization of helium using laser pulses with a wavelength of 394~nm and an intensity of $3\cdot10^{14}$W/cm$^2$. Those…
We investigate the existence of bound states and resonances in the ${\phi NN, J/\psi NN, \eta_c NN}$ systems using HAL QCD interactions for ${\phi N, J/\psi N}$, and ${\eta_c N}$. We employ the Gaussian expansion method to solve the…
Context: While classical models successfully reproduce intensities of many transition region lines, they predict helium EUV line intensities roughly an order of magnitude lower than the observed value. Aims: To determine the relevant…
Bound and resonance states of helium atom have been investigated inside a quantum dot by using explicitly correlated Hylleraas type basis set within the framework of stabilization method. To be specific, precise energy eigenvalues of bound…
Over the years many He-He interaction potentials have been developed, some very sophisticated, including various corrections beyond Born-Oppenheimer approximation. Most of them were used to predict properties of helium dimers and trimers,…
The shift and broadening of the resonance lines in spectrum of the antiprotonic helium atoms $\bar{p}\mathrm{He}^{+}$ located in fluid and superfluid $^4$He have been calculated. The contributions to the shift and broadening from collective…
Controlling the interactions between atoms with external fields opened up new branches in physics ranging from strongly correlated atomic systems to ideal Bose and Fermi gases and Efimov physics. Such control usually prepares samples that…
The resonance and bound--state poles of the amplitude describing elastic scattering of $\eta$-meson off the light nuclei $^2H$,\,$^3H$,\, $^3He$, and $^4He$ are calculated in the framework of a microscopic approach based on few--body…