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

Asymmetry in attosecond streaking from a degenerate state

Xiang-Ru Xiao, Hao Liang, Mu-Xue Wang, Liang-You Peng, Qihuang Gong

Published Aug 30, 2017• 1 citation
Publisher

Abstract

By the numerical solution to the time-dependent Schr\"odinger equation, we observe a remarkable asymmetry in the photoelectron streaking spectra when the ${\mathrm{He}}^{+}$ ion is ionized by an attosecond pulse from the $2s$ state in the presence of a weak infrared pulse. An analytical theory based on the modified perturbation theory is developed to quantitatively account for the underlying mechanism. We find that a transition occurs between the degenerate $2s$ and $2p$ states under the influence of the infrared electric field before the arrival of the attosecond pulse. The observed asymmetry in the attosecond streaking is formed by the interference of photoelectrons ionized from the $2s$ and $2p$ states. Using the sensitivity of the asymmetry to the infrared (IR) electric field at the moment of attosecond photoionization, we show that the present finding provides a highly reliable way to fully characterize the IR waveform in the streaking experiment.

DOI
10.1103/physreva.96.023428

Related papers

Steering continuum electron dynamics by low-energy attosecond streaking

Ji-Wei Geng, Wei-Hao Xiong, Xiang-Ru Xiao +2 more

A semiclassical model is developed to understand the electronic dynamics in the low-energy attosecond streaking. Under a relatively strong infrared (IR) pulse, the low-energy part of photoelectrons initialized by a single attosecond pulse (SAP) can either rescatter with the ionic core and induce interferences structures in the momentum spectra of the ionized electrons or be recaptured into the Rydberg states. The Coulomb potential plays essential roles in both the electron rescattering and recapturing processes. We find that by changing the time delay between the SAP and the IR pulse, the photoelectrons yield or the population of the Rydberg states can be effectively controlled. The present study demonstrates a fascinating way to steer the electron motion in the continuum.

Physical Review A•Aug 15, 2016•3 citations

Controlling backward-scattering photoelectron holography by attosecond streaking

Xiaoyang Yu, Min Li, Meng Han +1 more

We study the two-dimensional photoelectron momentum distribution in a synthesized field of an attosecond pulse and a weak infrared femtosecond pulse by solving the time-dependent Schr\"odinger equation of He atoms. The photoelectron momentum spectra reveal fruitful interference structures. With a semiclassical model, we show that some of the photoelectron interference structures come from the interference between the direct and backward-scattering electron trajectories. Those backward-scattering electrons are freed by the attosecond pulse and then are hard rescattered with parent ions by the streaking infrared field. By changing the phase delay between the attosecond pulse and the infrared laser field, we find that two kinds of backward-scattering electron trajectories will contribute to the holographic pattern. We show that backward-scattering holography can be explored with attosecond streaking experiments.

Physical Review A•Jul 20, 2018•10 citations

Directional loss of contrast by dephasing in temporal double-slit interferometry

Yusoff, M. A. H. B. Md, Harindranath B. Ambalampitiya, J. M. Ngoko Djiokap

Attosecond streaking camera is an ex situ technique in which a linearly polarized (LP) XUV attopulse produces an electron wavepacket by photoionization in the presence of an IR femtopulse. By moving the two synchronous oppositely circularly polarized XUV pulses (that make the ionizing LP pulse) apart in time, we propose an attosecond double-slit streak camera scheme to see information loss in polarization-dependent two-slit phenomena. Such streaking interferogram is then composed of several Feynman's thought experiments in time domain, in which electrons are affected by the IR pulse as they exit the two attoslits upon XUV ionization processes to form Archimedean spiral patterns. As a proof-of-principle, when the IR femtofield and first XUV attopulse are synchronous, a loss of contrast through dephasing is seen in the simulated momentum and energy distributions of the photoelectron. It is shown that the contrast between bright and dark interference fringes diminishes predominantly along the IR-field polarization axis and is sensitive to the IR-field waveform. Our which-time information scheme provides further confirmation of the wave-particle duality.

arXiv:2511.21094•Nov 26, 2025•0 citations

Theory of infrared-dressed atomic photoionization by extremely ultraviolet attosecond pulse trains

Han Chieh Lee, Shih-Da Jheng, Tsin Fu Jiang

We theoretically study the infrared (IR)-dressed photoionization of atoms excited by extreme ultraviolet attosecond pulse trains above ionization threshold. The initial state of atoms is treated perturbatively by the IR field, and the continuum states are considered as Coulomb–Volkov (CV) waves. CV waves can much reduce the gauge difference calculated with Volkov waves, and, in general, the contribution of ground-state perturbation to the photoelectron spectrum is negligible. Our calculations show qualitative agreement with the experimental results [Phys. Rev. Lett. 95, 013001 (2005)]. An evident dependence of the photoelectron spectrum on the delay phase between the IR field and the attosecond pulse train is exhibited in both helium and argon. The angular distribution of photoelectrons with various IR polarizations and the corresponding photoelectron spectra are presented. The linearly polarized IR fields are shown to have a higher controlling capability of the spectrum via IR delay phases than the circularly polarized fields. On the other hand, the circularly polarized IR fields have a fruitful angular dependence of photoelectrons with various IR delay phases.

Journal of the Optical Society of America B•Feb 10, 2012•5 citations

Theoretical study of attosecond chronoscopy of strong-field atomic photoionization

Andrey K. Kazansky, N M Kabachnik

A model which describes the time evolution of strong-field photoionization of atoms is presented. Based on the numerical solution of the non-stationary Schrodinger equation, the model allows one to predict and to interpret the results of experiments on double photoionization of atoms by a combined action of a very short (attosecond) XUV pulse and a few-cycle IR pulse of a powerful laser at various delay times between the two pulses. Depending on the binding energy of the ionized electron, two types of processes are considered. If the electron is tightly bound (Ne case), the XUV pulse ionizes the atom and shakes up another (outer) electron to an excited state, which is subsequently ionized by the strong IR field. For an atom with a weakly bound outer electron (Li case), the IR field ionizes the latter, while the XUV pulse, ionizing the inner shell, terminates (or suppresses) the strong-field ionization. In both cases the yield of doubly ionized ions strongly depends on the delay time between the two pulses, revealing 'steps', oscillations and other features which characterize the time evolution of the ionization process. The presented model describes qualitatively the results of recent experiments on Ne.

Journal of Physics B Atomic Molecular and Optical Physics•Jun 23, 2008•7 citations

Laser-assisted-autoionization dynamics of helium resonances with single attosecond pulses

Wei-Chun Chu, Song-Feng Zhao, C. D. Lin

The strong coupling between two autoionizing states in helium is studied theoretically with the pump-probe scheme. An isolated 100-as XUV pulse is used to excite helium near the $2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)$ resonance state in the presence of an intense infrared (IR) laser. The laser field introduces strong coupling between $2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)$ and $2{p}^{2}{(}^{1}\phantom{\rule{0.16em}{0ex}}S)$ states. The IR also can ionize helium from both autoionizing states. By changing the time delay between the XUV and the IR pulses, we investigated the photoelectron spectra near the two resonances. The results are used to explain the recent experiment by Gilbertson et al. [Phys. Rev. Lett. 105, 263003 (2010)]. Using the same isolated attosecond pulse and a 540-nm laser, we also investigate the strong coupling between $2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)$ and $2{s}^{2}{(}^{1}\phantom{\rule{0.16em}{0ex}}S)$ by examining how the photoelectron spectra are modified versus the time delay and the possibility of observing Autler-Townes doublet in such experiments.

arXiv:1205.4775•Physical Review A•Sep 29, 2011•40 citations
By the numerical solution to the time-dependent Schr"odinger equation, we observe a remarkable asymmetry in the photoelectron streaking spectra when the He+{\mathrm{He}}^{+}He+ ion is ionized by an attosecond pulse from the 2s2s2s state in the presence of a weak infrared pulse. An analytical theory based on the modified perturbation theory is developed to quantitatively account for the underlying mechanism. We find that a transition occurs between the degenerate 2s2s2s and 2p2p2p states under the influence of the infrared electric field before the arrival of the attosecond pulse. The observed asymmetry in the attosecond streaking is formed by the interference of photoelectrons ionized from the 2s2s2s and 2p2p2p states. Using the sensitivity of the asymmetry to the infrared (IR) electric field at the moment of attosecond photoionization, we show that the present finding provides a highly reliable way to fully characterize the IR waveform in the streaking experiment.
A semiclassical model is developed to understand the electronic dynamics in the low-energy attosecond streaking. Under a relatively strong infrared (IR) pulse, the low-energy part of photoelectrons initialized by a single attosecond pulse (SAP) can either rescatter with the ionic core and induce interferences structures in the momentum spectra of the ionized electrons or be recaptured into the Rydberg states. The Coulomb potential plays essential roles in both the electron rescattering and recapturing processes. We find that by changing the time delay between the SAP and the IR pulse, the photoelectrons yield or the population of the Rydberg states can be effectively controlled. The present study demonstrates a fascinating way to steer the electron motion in the continuum.
We study the two-dimensional photoelectron momentum distribution in a synthesized field of an attosecond pulse and a weak infrared femtosecond pulse by solving the time-dependent Schr\"odinger equation of He atoms. The photoelectron momentum spectra reveal fruitful interference structures. With a semiclassical model, we show that some of the photoelectron interference structures come from the interference between the direct and backward-scattering electron trajectories. Those backward-scattering electrons are freed by the attosecond pulse and then are hard rescattered with parent ions by the streaking infrared field. By changing the phase delay between the attosecond pulse and the infrared laser field, we find that two kinds of backward-scattering electron trajectories will contribute to the holographic pattern. We show that backward-scattering holography can be explored with attosecond streaking experiments.
Attosecond streaking camera is an ex situ technique in which a linearly polarized (LP) XUV attopulse produces an electron wavepacket by photoionization in the presence of an IR femtopulse. By moving the two synchronous oppositely circularly polarized XUV pulses (that make the ionizing LP pulse) apart in time, we propose an attosecond double-slit streak camera scheme to see information loss in polarization-dependent two-slit phenomena. Such streaking interferogram is then composed of several Feynman's thought experiments in time domain, in which electrons are affected by the IR pulse as they exit the two attoslits upon XUV ionization processes to form Archimedean spiral patterns. As a proof-of-principle, when the IR femtofield and first XUV attopulse are synchronous, a loss of contrast through dephasing is seen in the simulated momentum and energy distributions of the photoelectron. It is shown that the contrast between bright and dark interference fringes diminishes predominantly along the IR-field polarization axis and is sensitive to the IR-field waveform. Our which-time information scheme provides further confirmation of the wave-particle duality.
We theoretically study the infrared (IR)-dressed photoionization of atoms excited by extreme ultraviolet attosecond pulse trains above ionization threshold. The initial state of atoms is treated perturbatively by the IR field, and the continuum states are considered as Coulomb–Volkov (CV) waves. CV waves can much reduce the gauge difference calculated with Volkov waves, and, in general, the contribution of ground-state perturbation to the photoelectron spectrum is negligible. Our calculations show qualitative agreement with the experimental results [Phys. Rev. Lett. 95, 013001 (2005)]. An evident dependence of the photoelectron spectrum on the delay phase between the IR field and the attosecond pulse train is exhibited in both helium and argon. The angular distribution of photoelectrons with various IR polarizations and the corresponding photoelectron spectra are presented. The linearly polarized IR fields are shown to have a higher controlling capability of the spectrum via IR delay phases than the circularly polarized fields. On the other hand, the circularly polarized IR fields have a fruitful angular dependence of photoelectrons with various IR delay phases.
A model which describes the time evolution of strong-field photoionization of atoms is presented. Based on the numerical solution of the non-stationary Schrodinger equation, the model allows one to predict and to interpret the results of experiments on double photoionization of atoms by a combined action of a very short (attosecond) XUV pulse and a few-cycle IR pulse of a powerful laser at various delay times between the two pulses. Depending on the binding energy of the ionized electron, two types of processes are considered. If the electron is tightly bound (Ne case), the XUV pulse ionizes the atom and shakes up another (outer) electron to an excited state, which is subsequently ionized by the strong IR field. For an atom with a weakly bound outer electron (Li case), the IR field ionizes the latter, while the XUV pulse, ionizing the inner shell, terminates (or suppresses) the strong-field ionization. In both cases the yield of doubly ionized ions strongly depends on the delay time between the two pulses, revealing 'steps', oscillations and other features which characterize the time evolution of the ionization process. The presented model describes qualitatively the results of recent experiments on Ne.
The strong coupling between two autoionizing states in helium is studied theoretically with the pump-probe scheme. An isolated 100-as XUV pulse is used to excite helium near the 2s2p(1P)2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)2s2p(1P) resonance state in the presence of an intense infrared (IR) laser. The laser field introduces strong coupling between 2s2p(1P)2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)2s2p(1P) and 2p2(1S)2{p}^{2}{(}^{1}\phantom{\rule{0.16em}{0ex}}S)2p2(1S) states. The IR also can ionize helium from both autoionizing states. By changing the time delay between the XUV and the IR pulses, we investigated the photoelectron spectra near the two resonances. The results are used to explain the recent experiment by Gilbertson et al. [Phys. Rev. Lett. 105, 263003 (2010)]. Using the same isolated attosecond pulse and a 540-nm laser, we also investigate the strong coupling between 2s2p(1P)2s2p{(}^{1}\phantom{\rule{0.16em}{0ex}}P)2s2p(1P) and 2s2(1S)2{s}^{2}{(}^{1}\phantom{\rule{0.16em}{0ex}}S)2s2(1S) by examining how the photoelectron spectra are modified versus the time delay and the possibility of observing Autler-Townes doublet in such experiments.