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

Journal of Physics B Atomic Molecular and Optical Physics

Controlling the angular distribution of atomic photoelectrons in the region of laser-induced continuum structure in the femtosecond time domain

A N Grum-Grzhimailo, Alexey D. Kondorskiy, Klaus Bartschat

Published Nov 1, 2006• 21 citations
Publisher

Abstract

The influence of laser-induced continuum structure on the angular distribution of photoelectrons is studied in the femtosecond time domain by direct numerical solution of the time-dependent Schrodinger equation. Control of the photoelectron angular distribution is demonstrated for the hydrogen atom by coherent population transfer from the initial S-state to an excited D-state via the p-continuum and further ionization into the f-continuum states. A direct optimization procedure is used to find a domain of laser parameters, for which the efficiency of the control with respect to the time delay and energy detuning between the laser pulses is maximized.

DOI
10.1088/0953-4075/39/22/010

Related papers

Photoelectron Angular Distribution and Phase in Two-Photon Single Ionization of H and He by a Femtosecond and Attosecond Extreme-Ultraviolet Pulse

Kenichi L. Ishikawa, Kiyoshi Ueda

We theoretically study the photoelectron angular distribution (PAD) from the two-photon single ionization of H and He by femtosecond and attosecond extreme-ultraviolet pulses, based on the time-dependent perturbation theory and simulations with the full time-dependent Schrodinger equation. The PAD is formed by the interference of the s and d continuum wave packets, and, thus, contains the information on the relative phase and amplitude ratio between them. We find that, when a spectrally broadened femtosecond pulse is resonant with an excited level, the PAD substantially changes with pulse width, since the competition between resonant and nonresonant ionization paths, leading to distinct from the scattering phase shift difference, changes with it. In contrast, when the Rydberg manifold is excited, and for the case of above-threshold two-photon ionization, and the PAD do not depend much on pulse width, except for the attosecond region. Thus, the Rydberg manifold and the continuum behave similarly in this respect. For a high-harmonic pulse composed of multiple harmonic orders, while the value is different from that for a single-component pulse, the PAD still rapidly varies with pulse width. The present results illustrate a new way to tailor the continuum wave packet.

Applied Sciences•Mar 5, 2013•31 citations

Quantum coherent control of the photoelectron angular distribution in bichromatic-field ionization of atomic neon

Грызлова Елена Владимировна, Alexei N. Grum-Grzhimailo, Ekaterina I. Staroselskaya +2 more

We investigate the coherent control of the photoelectron angular distribution in bichromatic atomic ionization. Neon is selected as target since it is one of the most popular systems in current gas-phase experiments with free-electron lasers (FELSs). In particular, we tackle practical questions, such as the role of the fine-structure splitting, the pulse length, and the intensity. Time-dependent and stationary perturbation theory are employed, and we also solve the time-dependent Schr\"odinger equation in a single-active electron model. We consider neon ionized by a FEL pulse whose fundamental frequency is in resonance with either $2p\text{\ensuremath{-}}3s$ or $2p\text{\ensuremath{-}}4s$ excitation. The contribution of the nonresonant two-photon process and its potential constructive or destructive role for quantum coherent control is investigated.

arXiv:1712.00842•Physical Review A•Jan 26, 2018•29 citations

Modification of the photoelectron angular distribution through laser-induced continuum structure

Takashi Nakajima, Gabriela Buică

We theoretically investigate how the photoelectron angular distribution is altered by the introduction of a dressing laser. The physical mechanism underlying this alteration is the so-called laser-induced continuum structure; namely, a strong dressing laser induces quantum mechanical interference, the degree of which is different for different ionization channels. Therefore the branching ratio into different ionization channels changes as a function of laser detuning, and accordingly the photoelectron angular distribution is altered. After a general argument, we present specific theoretical results for the K atom, which indeed exhibit significant modification of the photoelectron angular distribution.

Physical Review A•Jan 19, 2005•10 citations

Control of interferences in an Autler-Townes doublet: Symmetry of control parameters

M. Wollenhaupt, Andreas Assion, O. Bazhan +5 more

Coherent control beyond population control and spectral interferences is demonstrated on the interferences and intensity of the two Autler-Townes (AT) components in the photoelectron spectrum of K atoms, using a sequence of two intense time-delayed femtosecond laser pulses. Photoelectron spectra were taken at various delay times between the two laser pulses and at different laser intensities at a fixed delay time. With respect to the interferences in the AT doublet the role of time delay and laser intensity is interchangeable for $(n+0.5)\ensuremath{\pi}$ excitation. Strong laser fields or the optical phase of the delayed laser pulse allow the quantum mechanical phase of an atomic state to be manipulated in a symmetrical fashion. The observations are discussed in terms of a two-level model coupled to the continuum. For suitable combinations of the laser intensity of the first pulse and the time delay, the second laser pulse leaves the excited state population unchanged.

Physical Review A•Jul 18, 2003•96 citations

Effects of laser polarization on photoelectron angular distribution through laser-induced continuum structure

Gabriela Buică, Takashi Nakajima

We theoretically investigate the effects of laser polarization on the photoelectron angular distribution through laser-induced continuum structure. We focus on a polarization geometry where the probe and dressing lasers are both linearly polarized and change the relative polarization angle between them. We find that the total ionization yield and the branching ratio into different ionization channels change as a function of the relative polarization angle, and accordingly the photoelectron angular distribution is altered. We present specific results for the $4{p}_{1∕2}\text{\ensuremath{-}}6{p}_{1∕2}$ and $4{p}_{3∕2}\text{\ensuremath{-}}6{p}_{3∕2}$ systems of the K atom and show that the change of the polarization angle leads to a significant modification of the photoelectron angular distribution.

arXiv:1302.0645•Physical Review A•Nov 30, 2005•1 citation

Coherent control of the photoelectron angular distribution in ionization of neon by a circularly polarized bichromatic field in the resonance region

Грызлова Елена Владимировна, Maria M. Popova, Alexei N. Grum-Grzhimailo +3 more

Coherent control of the photoelectron angular distribution (PAD) in ionization by a bichromatic circularly polarized field is theoretically studied in neon in the photon energy range 16--20 eV. The breakdown of the PAD axial symmetry with respect to the light propagation direction is analyzed. The coherent control of the PAD manifests itself through: (1) a change from a one-lobe to a three-lobe shape, respectively, for co- and counter-rotating harmonics, (2) a variation of the polar asymmetry with the light frequency, and (3) a rotation of the PAD around the direction of the beam depending on the relative phase between the harmonics. Tuning the lowest harmonic at the $2{p}^{5}3s$ or $2{p}^{5}4s$ intermediate excited states strongly influences the PAD. In contrast to atomic hydrogen and the alkali atoms, the cases of equal and opposite helicity are not related in neon. Features of a conjugate polarization setup, when one harmonic is linearly polarized while the other one is circularly polarized, are also discussed.

Physical Review A•Dec 12, 2019•15 citations
The influence of laser-induced continuum structure on the angular distribution of photoelectrons is studied in the femtosecond time domain by direct numerical solution of the time-dependent Schrodinger equation. Control of the photoelectron angular distribution is demonstrated for the hydrogen atom by coherent population transfer from the initial S-state to an excited D-state via the p-continuum and further ionization into the f-continuum states. A direct optimization procedure is used to find a domain of laser parameters, for which the efficiency of the control with respect to the time delay and energy detuning between the laser pulses is maximized.
We theoretically study the photoelectron angular distribution (PAD) from the two-photon single ionization of H and He by femtosecond and attosecond extreme-ultraviolet pulses, based on the time-dependent perturbation theory and simulations with the full time-dependent Schrodinger equation. The PAD is formed by the interference of the s and d continuum wave packets, and, thus, contains the information on the relative phase and amplitude ratio between them. We find that, when a spectrally broadened femtosecond pulse is resonant with an excited level, the PAD substantially changes with pulse width, since the competition between resonant and nonresonant ionization paths, leading to distinct from the scattering phase shift difference, changes with it. In contrast, when the Rydberg manifold is excited, and for the case of above-threshold two-photon ionization, and the PAD do not depend much on pulse width, except for the attosecond region. Thus, the Rydberg manifold and the continuum behave similarly in this respect. For a high-harmonic pulse composed of multiple harmonic orders, while the value is different from that for a single-component pulse, the PAD still rapidly varies with pulse width. The present results illustrate a new way to tailor the continuum wave packet.
We investigate the coherent control of the photoelectron angular distribution in bichromatic atomic ionization. Neon is selected as target since it is one of the most popular systems in current gas-phase experiments with free-electron lasers (FELSs). In particular, we tackle practical questions, such as the role of the fine-structure splitting, the pulse length, and the intensity. Time-dependent and stationary perturbation theory are employed, and we also solve the time-dependent Schr\"odinger equation in a single-active electron model. We consider neon ionized by a FEL pulse whose fundamental frequency is in resonance with either $2p\text{\ensuremath{-}}3s$ or $2p\text{\ensuremath{-}}4s$ excitation. The contribution of the nonresonant two-photon process and its potential constructive or destructive role for quantum coherent control is investigated.
We theoretically investigate how the photoelectron angular distribution is altered by the introduction of a dressing laser. The physical mechanism underlying this alteration is the so-called laser-induced continuum structure; namely, a strong dressing laser induces quantum mechanical interference, the degree of which is different for different ionization channels. Therefore the branching ratio into different ionization channels changes as a function of laser detuning, and accordingly the photoelectron angular distribution is altered. After a general argument, we present specific theoretical results for the K atom, which indeed exhibit significant modification of the photoelectron angular distribution.
Coherent control beyond population control and spectral interferences is demonstrated on the interferences and intensity of the two Autler-Townes (AT) components in the photoelectron spectrum of K atoms, using a sequence of two intense time-delayed femtosecond laser pulses. Photoelectron spectra were taken at various delay times between the two laser pulses and at different laser intensities at a fixed delay time. With respect to the interferences in the AT doublet the role of time delay and laser intensity is interchangeable for $(n+0.5)\ensuremath{\pi}$ excitation. Strong laser fields or the optical phase of the delayed laser pulse allow the quantum mechanical phase of an atomic state to be manipulated in a symmetrical fashion. The observations are discussed in terms of a two-level model coupled to the continuum. For suitable combinations of the laser intensity of the first pulse and the time delay, the second laser pulse leaves the excited state population unchanged.
We theoretically investigate the effects of laser polarization on the photoelectron angular distribution through laser-induced continuum structure. We focus on a polarization geometry where the probe and dressing lasers are both linearly polarized and change the relative polarization angle between them. We find that the total ionization yield and the branching ratio into different ionization channels change as a function of the relative polarization angle, and accordingly the photoelectron angular distribution is altered. We present specific results for the $4{p}_{1∕2}\text{\ensuremath{-}}6{p}_{1∕2}$ and $4{p}_{3∕2}\text{\ensuremath{-}}6{p}_{3∕2}$ systems of the K atom and show that the change of the polarization angle leads to a significant modification of the photoelectron angular distribution.
Coherent control of the photoelectron angular distribution (PAD) in ionization by a bichromatic circularly polarized field is theoretically studied in neon in the photon energy range 16--20 eV. The breakdown of the PAD axial symmetry with respect to the light propagation direction is analyzed. The coherent control of the PAD manifests itself through: (1) a change from a one-lobe to a three-lobe shape, respectively, for co- and counter-rotating harmonics, (2) a variation of the polar asymmetry with the light frequency, and (3) a rotation of the PAD around the direction of the beam depending on the relative phase between the harmonics. Tuning the lowest harmonic at the 2p53s2{p}^{5}3s2p53s or 2p54s2{p}^{5}4s2p54s intermediate excited states strongly influences the PAD. In contrast to atomic hydrogen and the alkali atoms, the cases of equal and opposite helicity are not related in neon. Features of a conjugate polarization setup, when one harmonic is linearly polarized while the other one is circularly polarized, are also discussed.