Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Line-profile considerations of resonant multiphoton ionization

S. N. Dixit, P. Lambropoulos

Published Apr 1, 1979• 8 citations
Publisher

Abstract

It is shown that the interpretation of the line profile of resonant multiphoton ionization in terms of a Fano profile with a constant background can lead to difficulties. These difficulties are related to the fact that the nonresonant background may exhibit considerable structure as a function of photon frequency.
DOI
10.1103/physreva.19.1576

Related papers

Resonant multiphoton ionization via the Fano autoionization formalism

Lloyd Armstrong, Brian Lee Beers, S. Feneuille

We introduce an analogy between the theory of autoionizing states as described by Fano and the theory of certain states ("pseudo-autoionizing states") of an irradiated atom. These "pseudo-autoionizing states" are used to obtain a number of qualitative results concerning resonant multiphoton ionization probabilities for several experimental arrangements. This method makes clear the importance of nonresonant processes in determining resonant multiphoton ionization line shapes.

Physical Review A•Nov 1, 1975•138 citations

Deviation from the Fano profile in resonance-enhanced multiphoton autoionization

Lipika Adhya, Krishna Rai Dastidar

We know that the Fano profile is obtained for single-photon absorption to the ionization continuum in the presence of an autoionizing state. We have shown that, in the case of (1+1)-photon absorption to an autoionizing state embedded in the ionization continuum, the absorption profile changes radically to a mirror image of the Fano profile for the value of q=\ifmmode\pm\else\textpm\fi{}1, q being the Fano q parameter. Moreover, for higher values of q, the (1+1)-photon absorption profile exhibits a broad minimum, while a distinct interference pattern is obtained in the profile of single-photon absorption. The absorption line shape has been found to oscillate between the Fano and a modified Fano profile for the autoionization through odd and even number of steps, respectively, via resonances.

Physical Review A•Oct 1, 1994•11 citations

Short-time behavior in multiphoton ionization

Constantine E. Theodosiou, Lloyd Armstrong, Michele Crance +1 more

The short-time behavior of atomic multiphoton-ionization profiles is investigated using simplified models of the field and the atom. The importance of including many levels in the model atom, of spontaneous emission, and of pulse shape are studied in detail. It is shown that the first two of these have little influence on the qualitative behavior of the short-time behavior of the resonance profile, but that the third, the pulse shape, is critical in determining the time evolution of the resonance profile.

Physical Review A•Feb 1, 1979•51 citations

Photoionization of atomic hydrogen in electric fields: lineshapes

Alexander Alijah, A von Hopffgarten

Fano- and Lorentz-type profile formulae are tested for Stark resonances against exact quantum results. If background terms are included, both work very satisfactorily for a wide range of resonances.

Journal of Physics B Atomic Molecular and Optical Physics•Mar 14, 1994•6 citations

Dual Fano and Lorentzian line profile properties of autoionizing states

B. Tu, Jun Xiao, Ke Yao +15 more

Photon absorption spectroscopy is a powerful tool for uncovering the structure of atoms, molecules, and solids. Symmetric Lorentzian and asymmetric Fano line shapes are fundamental spectroscopic signatures related to the structural and dynamical properties. Recently, Ott et al. [Science 340, 716 (2013)] successfully transferred Fano profile into Lorentzian line shape using an intense infrared laser, after excitation of autoionizing states in helium by attosecond XUV pulse. This is a very important step forward in quantum phase control. However, here we show experimentally that an autoionizing state can have both Fano and Lorentzian behavior naturally, depending on the process involved. This study utilized the inverse process of photon absorption ionization, i.e., electron ion recombination with photon emission, making sure the resonant autoionizing state is not modified or decorated by the laser fields. Our result implies that excitation of the state through different paths---for example, one photon versus multiphoton excitation, or even one step versus multistep excitation---can lead to different Fano profiles for the same resonant state. We also report an experimental determination of the energy shifts in the recombination photon-intensity peaks due to the interference between the resonant and nonresonant processes.

Physical Review A•Jun 22, 2015•10 citations

Influence of excitation pulse characteristics on resonant multiphoton ionization

Michele Crance, S. Feneuille

The object of this letter is to show that, in some limiting cases, a simple model using an atomic density operator and a classical description of the field allows one to study the influence of the characteristics (duration and shape) of the excitation pulse on resonant multiphoton ionization.

Journal de Physique Lettres•Jan 1, 1976•11 citations
We know that the Fano profile is obtained for single-photon absorption to the ionization continuum in the presence of an autoionizing state. We have shown that, in the case of (1+1)-photon absorption to an autoionizing state embedded in the ionization continuum, the absorption profile changes radically to a mirror image of the Fano profile for the value of q=\ifmmode\pm\else\textpm\fi{}1, q being the Fano q parameter. Moreover, for higher values of q, the (1+1)-photon absorption profile exhibits a broad minimum, while a distinct interference pattern is obtained in the profile of single-photon absorption. The absorption line shape has been found to oscillate between the Fano and a modified Fano profile for the autoionization through odd and even number of steps, respectively, via resonances.
The short-time behavior of atomic multiphoton-ionization profiles is investigated using simplified models of the field and the atom. The importance of including many levels in the model atom, of spontaneous emission, and of pulse shape are studied in detail. It is shown that the first two of these have little influence on the qualitative behavior of the short-time behavior of the resonance profile, but that the third, the pulse shape, is critical in determining the time evolution of the resonance profile.
Photon absorption spectroscopy is a powerful tool for uncovering the structure of atoms, molecules, and solids. Symmetric Lorentzian and asymmetric Fano line shapes are fundamental spectroscopic signatures related to the structural and dynamical properties. Recently, Ott et al. [Science 340, 716 (2013)] successfully transferred Fano profile into Lorentzian line shape using an intense infrared laser, after excitation of autoionizing states in helium by attosecond XUV pulse. This is a very important step forward in quantum phase control. However, here we show experimentally that an autoionizing state can have both Fano and Lorentzian behavior naturally, depending on the process involved. This study utilized the inverse process of photon absorption ionization, i.e., electron ion recombination with photon emission, making sure the resonant autoionizing state is not modified or decorated by the laser fields. Our result implies that excitation of the state through different paths---for example, one photon versus multiphoton excitation, or even one step versus multistep excitation---can lead to different Fano profiles for the same resonant state. We also report an experimental determination of the energy shifts in the recombination photon-intensity peaks due to the interference between the resonant and nonresonant processes.