Related papers: Cross sections for short pulse single and double i…
We calculate the distributions in recoil momenta and their energy distributions for the high energy non-relativistic double photoionization of helium caused by the quasifree mechanism of the process. The distributions obtain local maxima at…
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…
We present a time dependent quantum calculation of the scattering of a few-photon pulse on a single atom. The photon wave packet is assumed to propagate in a transversely strongly confined geometry, which ensures strong atom-light coupling…
Using the eigenchannel R-matrix method we calculate partial photoionization cross sections from the ground state of the helium atom for incident photon energies up to the N=9 manifold. The wide energy range covered by our calculations…
Realistic attosecond wave packets have complex profiles that, in dispersive conditions, rapidly broaden or split into multiple components. Such behaviors are encoded in sharp features of the wave packet spectral phase. Here, we exploit the…
Stimulated by a recent measurement of coherent control in photoionization of atomic barium, we have calculated one- and two-photon ionization cross sections of the aligned 6s6p^1P_1 state of barium in the energy range between the 5d_{3/2}…
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…
We present an efficient method for modeling the single and double ionization dynamics of the H$_2$ molecule in ultrashort intense laser fields. This method is based on a semi-analytical approach to calculate the time-dependent single and…
We describe the interaction of two two-level atoms in free space with propagating modes of the quantized electromagnetic field, using the time-dependent Heisenberg-Langevin method. For single- photon pulses, we consider the effect of the…
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…
In anticipation of upcoming two-photon double ionization of atoms and particularly Helium, under strong short wavelength radiation sources (45 eV), we present quantitative signatures of direct two-photon double ejection, in the…
A simple model for sequential multiphoton ionization by ultra-intense x-rays is presented. The derived scaling of the ion yield with pulse energy quantitatively reproduces the experimental data, which shows that the ion yield increases…
Photoelectron energy spectra resulting by the interaction of hydrogen with two short pulses having carrier frequencies, respectively, in the range of the infrared and XUV regions have been calculated. The effects of the pulse duration and…
We investigate the possibility to use transient absorption of a coherent bound electron wave packet in hydrogen as an attosecond pulse characterization technique. In recent work we have shown that photoionization of such a coherent bound…
The ionization of atoms with sequences of attosecond pulses gives rise to excited ionic states that are entangled with the emitted photoelectron. Still, the ionic ensemble preserves some coherence that can be controlled through the laser…
Photoelectron angular distributions (PADs) obtained from ionization of potassium atoms using moderately intense femtosecond IR fields ($\sim$10$^{12}$Wcm$^{-2}$) of various polarization states are shown to provide a route to "complete"…
We report on non-sequential double ionization of Ar by a laser pulse consisting of two counter rotating circularly polarized fields (390 nm and 780 nm). The double ionization probability depends strongly on the relative intensity of the two…
We apply the convergent close-coupling (CCC) formalism to the problem of two-photon double ionization of helium. The electron-photon interaction is treated perturbatively whereas the electron-electron interaction is included in full. The…
We investigate laser-induced nonsequential double ionization by a polarization-gated laser pulse, constructed employing two counter-rotating circularly polarized few cycle pulses with a time delay $T_{d}$. We address the problem within a…
A unitary model describing the electronic transitions in an atom subject to a strong high frequency laser pulse is proposed. The model fully accounts for the initial state coupling with the continuum spectrum. Continuum-continuum as well as…