Related papers: Attosecond electron-spin dynamics in Xe 4d photoio…
We investigated the giant resonance in Xenon by high-order harmonic generation spectroscopy driven by a two-color field. The addition of a non-perturbative second harmonic component parallel to the driving field breaks the symmetry between…
Upon absorbing a photon, the ionized electron sails through the target force field in attoseconds to reach free space. This navigation probes details of the potential landscape that get imprinted into the phase of the ionization amplitude.…
Chiral light-matter interactions have been investigated for two centuries, leading to the discovery of many chiroptical processes used for discrimination of enantiomers. Whereas most chiroptical effects result from a response of bound…
We investigate the time-dependent evolution of the dipole phase shift induced by strong-field ionization (SFI) using attosecond transient absorption spectroscopy (ATAS) for time-delays where the pump-probe pulses overlap. We study measured…
Photoionization of the I$^+$ ion in the energy range of the 4d giant resonance has been studied using our recently developed random-phase approximation with exchange (RPAE) method. Photoionization cross sections for the I$^+$ $4d-\epsilon…
We demonstrate that strong-field ionization of atoms in circularly polarized laser fields generates a photoelectron spin texture with toroidal topology in momentum space. Using time-dependent Schr\"odinger equation simulations,…
The dissociation dynamics of the $\tilde{A}$-state of ammonia have been studied using a resonant multiphoton ionisation probe in a photoelectron spectroscopy experiment. The use of a resonant intermediate in the multiphoton ionisation…
The absolute generalized cross sections and angular distribution parameters of photoelectrons for the two-photon above threshold $3p$-ionization of Ar were calculated in the exciting photon energy range from 15.76 to 36 eV. The correlation…
We investigate ionization of neon atoms by an isolated attosecond pump pulse in the presence of two coherent extreme ultraviolet or x-ray probe fields. The probe fields are tuned to a core-valence transition in the residual ion and induce…
We study the photoionization of argon atoms close to the 3s$^2$3p$^6$ $\rightarrow$ 3s$^1$3p$^6$4p $\leftrightarrow$ 3s$^2$3p$^5$ $\varepsilon \ell$, $\ell$=s,d Fano window resonance. An interferometric technique using an attosecond pulse…
Using the photon-ion merged-beams technique at a synchrotron light source, we have measured relative cross sections for single and up to five-fold photoionization of Fe$^{2+}$ ions in the energy range 690--920 eV. This range contains…
It is commonly accepted that the magnitude of a photoelectron circular dichroism (PECD) is governed by the ability of an outgoing photoelectron wave packet to probe the chiral asymmetry of a molecule. To be able to accumulate this…
We demonstrate for the first time that the effect of fullerene shell upon photoionization of the "caged" atom in an endohedral can result in formation of Giant Endohedral Resonances or GER. This is illustrated by the concrete case of Xe@C60…
Agreement between theoretical calculations of atomic structure and spectroscopic measurements is used to constrain possible contribution of exotic spin-dependent interactions between electrons to the energy differences between states in…
When atoms and molecules are irradiated by an x-ray free-electron laser (XFEL), they are highly ionized via a sequence of one-photon ionization and relaxation processes. To describe the ionization dynamics during XFEL pulses, a rate…
Fundamental quantum transition time scales are accessible through the spin polarization of photoelectrons coming from initially spin-degenerate states for solid-state materials . In this work we investigate the modification of this time…
We report on a combined experimental and theoretical study of XUV ionization of atomic argon in the presence of a near-infrared laser field. The resulting energy- and angle- resolved photoemission spectra have been described in the…
Attosecond charge migration is a periodic evolution of the charge density of a molecule on a time scale defined by the energy intervals between the electronic states involved. Here, we report the observation of charge migration in neutral…
Using a spectrally resolved electron interferometry technique, we measure photoionization time delays between the $3s$ and $3p$ subshells of argon over a large 34-eV energy range covering the Cooper minima in both subshells. The observed…
Fullerenes have unique physical and chemical properties that are associated with their delocalized conjugated electronic structure. Among them, there is a giant ultra-broadband - and therefore ultrafast - plasmon resonance, which for…