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

Chinese Physics B

Multiphoton resonant ionization of hydrogen atom exposed to two-colour laser pulses

Peijie Wang, Fang Yan

Published Oct 1, 2008• 4 citations
Publisher

Abstract

This paper studies the multiphoton resonant ionization by two-colour laser pulses in the hydrogen atom by solving the time-dependent Schrodinger equation. By fixing the parameters of fundamental laser field and scanning the frequency of second laser field, it finds that the ionization probability shows several resonance peaks and is also much larger than the linear superposition of probabilities by applying two lasers separately. The enhancement of the ionization happens when the system is resonantly pumped to the excited states by absorbing two or more colour photons non-sequentially.

DOI
10.1088/1674-1056/17/10/023

Related papers

The intensity dependence of Rydberg state excitation in the strong field ionization of hydrogen atoms by two-color laser fields

Shijia Liu, Zhaoyan Zhou

To study the physical mechanism of atomic Rydberg state excitation (RSE) in two-color laser fields, we solve the time-dependent Schrödinger equation (TDSE) to calculate the ionization and excitation of hydrogen atoms. The relationship between the excited state population and the excitation rate of hydrogen atoms and the intensity of the fundamental frequency (FW) field can be observed by adjusting the laser intensity of the second harmonic (SH) field. The results demonstrate that multiphoton resonance absorption aligns with the physical mechanism of atomic resonant state excitation in two-color laser fields.

Optics Young Scientist Summit (OYSS)•Dec 29, 2023•0 citations

Phase control in two-colour multiphoton ionization

M. Protopapas, P. L. Knight

We examine the excitation dynamics of a model atom excited by a two-colour laser field. Here the two colours or frequencies are the fundamental and its third harmonic. The atomic model consists of two bound states which are near-resonantly coupled by a three-photon excitation by the fundamental and a one-photon excitation by the third harmonic, and a structureless continuum. We investigate how the laser parameters (intensity and frequency) and the relative phase between the two colours affects the degree of phase modulation in the ionization signal. We compare our findings from this simple model atom with those from more realistic atomic models by carrying out numerical integration of the hydrogenic Schrodinger equation in both one and three dimensions.

Journal of Physics B Atomic Molecular and Optical Physics•Oct 28, 1995•33 citations

Resonant multiphoton ionization of the 1s state of a hydrogen atom in a strong laser field

Ekaterina A. Volkova, A. M. Popov, Olga V. Tikhonova

The process of resonant multiphoton ionization of a hydrogen atom in the ground 1 s state is studied by direct numerical integration of the nonstationary Schrödinger equation for a quantum system in an electromagnetic field. The dependence of photoionization probability on the radiation intensity is found to be nonmonotonic. It is established that the minima of ionization correspond to multiphoton resonances between the ground state and one of the excited (Rydberg) atomic states perturbed by the laser field. It is shown that ionization is suppressed due to rearrangement of Rydberg states in a strong electromagnetic field and is accompanied by efficient Raman Λ transitions, which connect a set of closely lying Rydberg states via the continuum.

Optics and Spectroscopy•Jan 1, 2000•8 citations

Resonant multiphoton ionization of atomic hydrogen

Yves Gontier, N. K. Rahman, M. Trahin

The resonantly enhanced multiphoton ionization of atomic hydrogen is studied for the case of four-photon ionization (three-photon resonant). The time-dependent probabilities, the shape of the resonance profile at different intensities, and the nonlinear index are computed for coherent light at frequencies around the resonance (365 nm). The systematic dependence of the cross section as a function of the principal quantum number of the resonant state (as this tends towards the Rydberg states) is investigated at zero detuning. The probabilities of absorption of one photon more than necessary for the four-photon ionization process (resonantly enhanced above-threshold ionization) is computed and the relevant branching ratios are examined. Then it is shown that the effect of the spatio-temporal structures of the laser pulse is to red shift the maximum of the resonance profile, whereas that of an ideal chaotic light is to blue shift and broaden the resonance peak. The shape, shift, and width of the profile resulting from both these effects are in very fair agreement with the experimental ones.

Physical Review A•Jun 1, 1988•15 citations

Resonance enhancement of above-threshold peaks in multiphoton ionization

Martin Dörr, Robin Shakeshaft

We have solved the time-dependent Schr\"odinger equation for a one-dimensional model atom exposed to a spatially homogeneous laser field that is turned on smoothly. We have studied the ionization of this "atom" at a laser frequency close to a three-photon resonance and have found a spike on top of each of the above-threshold peaks of the ionization signal, in accordance with the findings of a recent experimental investigation.

Physical Review A•Jul 1, 1988•26 citations

Two-color above-threshold ionization of atoms

C. S. Han

A nonperturbative method is used to study the two-color multiphoton ionization of atoms by solving the Schr\"odinger equation in momentum space, which facilitates the extraction of the rapidly varying part of the wave function. Our method generalizes the problem for cases where an arbitrary number of ionization photons are absorbed, and also takes into account the threshold shifts due to both the high- and low-frequency fields. The photoelectron energy spectra of the hydrogen atoms are calculated and the dependence on the laser field strengths and frequencies is discussed. \textcopyright{} 1996 The American Physical Society.

Physical Review A•Jun 1, 1996•5 citations
This paper studies the multiphoton resonant ionization by two-colour laser pulses in the hydrogen atom by solving the time-dependent Schrodinger equation. By fixing the parameters of fundamental laser field and scanning the frequency of second laser field, it finds that the ionization probability shows several resonance peaks and is also much larger than the linear superposition of probabilities by applying two lasers separately. The enhancement of the ionization happens when the system is resonantly pumped to the excited states by absorbing two or more colour photons non-sequentially.
To study the physical mechanism of atomic Rydberg state excitation (RSE) in two-color laser fields, we solve the time-dependent Schrödinger equation (TDSE) to calculate the ionization and excitation of hydrogen atoms. The relationship between the excited state population and the excitation rate of hydrogen atoms and the intensity of the fundamental frequency (FW) field can be observed by adjusting the laser intensity of the second harmonic (SH) field. The results demonstrate that multiphoton resonance absorption aligns with the physical mechanism of atomic resonant state excitation in two-color laser fields.
We examine the excitation dynamics of a model atom excited by a two-colour laser field. Here the two colours or frequencies are the fundamental and its third harmonic. The atomic model consists of two bound states which are near-resonantly coupled by a three-photon excitation by the fundamental and a one-photon excitation by the third harmonic, and a structureless continuum. We investigate how the laser parameters (intensity and frequency) and the relative phase between the two colours affects the degree of phase modulation in the ionization signal. We compare our findings from this simple model atom with those from more realistic atomic models by carrying out numerical integration of the hydrogenic Schrodinger equation in both one and three dimensions.
The process of resonant multiphoton ionization of a hydrogen atom in the ground 1 s state is studied by direct numerical integration of the nonstationary Schrödinger equation for a quantum system in an electromagnetic field. The dependence of photoionization probability on the radiation intensity is found to be nonmonotonic. It is established that the minima of ionization correspond to multiphoton resonances between the ground state and one of the excited (Rydberg) atomic states perturbed by the laser field. It is shown that ionization is suppressed due to rearrangement of Rydberg states in a strong electromagnetic field and is accompanied by efficient Raman Λ transitions, which connect a set of closely lying Rydberg states via the continuum.
The resonantly enhanced multiphoton ionization of atomic hydrogen is studied for the case of four-photon ionization (three-photon resonant). The time-dependent probabilities, the shape of the resonance profile at different intensities, and the nonlinear index are computed for coherent light at frequencies around the resonance (365 nm). The systematic dependence of the cross section as a function of the principal quantum number of the resonant state (as this tends towards the Rydberg states) is investigated at zero detuning. The probabilities of absorption of one photon more than necessary for the four-photon ionization process (resonantly enhanced above-threshold ionization) is computed and the relevant branching ratios are examined. Then it is shown that the effect of the spatio-temporal structures of the laser pulse is to red shift the maximum of the resonance profile, whereas that of an ideal chaotic light is to blue shift and broaden the resonance peak. The shape, shift, and width of the profile resulting from both these effects are in very fair agreement with the experimental ones.
A nonperturbative method is used to study the two-color multiphoton ionization of atoms by solving the Schr\"odinger equation in momentum space, which facilitates the extraction of the rapidly varying part of the wave function. Our method generalizes the problem for cases where an arbitrary number of ionization photons are absorbed, and also takes into account the threshold shifts due to both the high- and low-frequency fields. The photoelectron energy spectra of the hydrogen atoms are calculated and the dependence on the laser field strengths and frequencies is discussed. \textcopyright{} 1996 The American Physical Society.