Journal: Journal of Physics B: Atomic, Molecular and Optical Physics

Abbreviation

J. Phys. B: At. Mol. Opt. Phys

Publisher

IOP Publishing

Journal Volumes

ISSN

1361-6455
0368-3508
0953-4075
0022-3700

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Publications 1 - 10 of 58
  • Stark deceleration of hydrogen atoms
    Item type: Journal Article
    Vliegen, E.; Merkt, Frédéric (2006)
    Journal of Physics B: Atomic, Molecular and Optical Physics
  • Slow beams of atomic hydrogen by multistage Zeeman deceleration
    Item type: Journal Article
    Hogan, Stephen D.; Wiederkehr, Alex W.; Andrist, Markus; et al. (2008)
    Journal of Physics B: Atomic, Molecular and Optical Physics
    Hydrogen atoms seeded in a supersonic expansion of Kr have been decelerated from an initial velocity of 435 m s−1 to 107 m s−1 in a multistage Zeeman decelerator. The operation of the decelerator has been fully quantified by numerical particle trajectory simulations and independent measurements of the velocity distribution by ion time-of-flight mass spectrometry following photoionization of the decelerated atoms. The velocity distributions of the decelerated atom clouds have a half-width at half-maximum of 25 ± 12 m s−1 corresponding to a temperature of ~30 mK. These velocities and temperatures are sufficiently low that magnetic trapping of the atoms can be envisaged.
  • Determination of the ionization energy of krypton by Rydberg-state-resolved threshold-ionization spectroscopy
    Item type: Journal Article
    Hollenstein, U.; Seiler, R.; Merkt, Frédéric (2003)
    Journal of Physics B: Atomic, Molecular and Optical Physics
  • Relativistic kinetic-balance condition for explicitly correlated basis functions
    Item type: Journal Article
    Simmen, Benjamin; Mátyus, Edit; Reiher, Markus (2015)
    Journal of Physics B: Atomic, Molecular and Optical Physics
  • High Rydberg states of argon: Stark effect and field ionization properties
    Item type: Journal Article
    Merkt, Frédéric; Osterwalder, Andreas; Seiler, Robert; et al. (1998)
    Journal of Physics B: Atomic, Molecular and Optical Physics
  • Roadmap on photonic, electronic and atomic collision physics: III. Heavy particles: with zero to relativistic speeds
    Item type: Journal Article
    Aumayr, Friedrich; Ueda, Kiyoshi; Sokell, Emma; et al. (2019)
    Journal of Physics B: Atomic, Molecular and Optical Physics
    We publish three Roadmaps on photonic, electronic and atomic collision physics in order to celebrate the 60th anniversary of the ICPEAC conference. Roadmap III focusses on heavy particles: with zero to relativistic speeds. Modern theoretical and experimental approaches provide detailed insight into the wide range of many-body interactions involving projectiles and targets of varying complexity ranging from simple atoms, through molecules and clusters, complex biomolecules and nanoparticles to surfaces and crystals. These developments have been driven by technological progress and future developments will expand the horizon of the systems that can be studied. This Roadmap aims at looking back along the road, explaining the evolution of the field, and looking forward, collecting nineteen contributions from leading scientists in the field.
  • Quantitative uncertainty analysis of extracting attosecond delays from spectrally overlapping RABBIT experiments
    Item type: Journal Article
    Ji, Jia-Bao; Wörner, Hans Jakob (2025)
    Journal of Physics B: Atomic, Molecular and Optical Physics
    A two-dimensional spectrogram with oscillations along the temporal dimension and partially overlapping peaks along the spectral dimension is the typical outcome of interferometric measurements, e.g. the reconstruction of attosecond beating by interference of two-photon transitions experiment of complex systems. It is necessary to retrieve the oscillation phases of the individual components in order to extract the attosecond photoionisation time delays. One can use either the global-fit method (simulating the oscillations of each component and adding them together) or the complex-fit method (first Fourier transforming along the temporal dimension and then fitting the Fourier coefficients at the relevant frequency in the spectral dimension). Here, we prove that the two methods are mathematically equivalent in the frame of least-squares fitting, and we derive the formula for the variance of the extracted phases based on the Poisson distribution. The fitting and the uncertainty formula are not limited to specific peak shapes. For the special case of two Gaussian peaks, there is a relatively simple expression for the phase uncertainty. The method can be further extended to fitting with peaks that have known phase structures or peaks with relative phase constraints. The uncertainty formula (with multiple peaks and a background) is verified by numerical simulations, and the results show that phase retrieval is possible as long as the peaks do not fully overlap (having exactly the same shape, position and phase structure), although the uncertainty rises with the degree of overlap. We also find that the correctness of fitting relies on properly assigning all the peaks in the energy domain, which is particularly important for extracting the phase from a relatively weak peak overlapped with other peaks.
  • Comparison of different approaches to the longitudinal momentum spread after tunnel ionization
    Item type: Journal Article
    Hofmann, C.; Landsman, A. S.; Cirelli, C.; et al. (2013)
    Journal of Physics B: Atomic, Molecular and Optical Physics
  • Analytical expression for continuum–continuum transition amplitude of hydrogen-like atoms with angular-momentum dependence
    Item type: Journal Article
    Ji, Jia-Bao; Ueda, Kiyoshi; Han, Meng; et al. (2024)
    Journal of Physics B: Atomic, Molecular and Optical Physics
    Attosecond chronoscopy typically utilises interfering two-photon transitions to access the phase information. Simulating these two-photon transitions is challenging due to the continuum–continuum transition term. The hydrogenic approximation within second-order perturbation theory has been widely used due to the existence of analytical expressions of the wave functions. So far, only (partially) asymptotic results have been derived, which fail to correctly describe the low-kinetic-energy behaviour, especially for high angular-momentum states. Here, we report an analytical expression that overcomes these limitations. It is based on the Appell’s F1 function and uses the confluent hypergeometric function of the second kind as the intermediate state. We show that the derived formula quantitatively agrees with the numerical simulations using the time-dependent Schrödinger equation for various angular-momentum states, which improves the accuracy compared to the other analytical approaches that were previously reported. Furthermore, we give an angular-momentum-dependent asymptotic form of the outgoing wavefunction and the corresponding continuum–continuum dipole transition amplitudes.
  • High-resolution laser absorption spectroscopy in the extreme ultraviolet
    Item type: Journal Article
    Sommavilla, Marcel; Hollenstein, Urs; Greetham, Gregory M.; et al. (2002)
    Journal of Physics B: Atomic, Molecular and Optical Physics
Publications 1 - 10 of 58