Molecular photoelectron angular distribution rotations in multiphoton resonant ionization of H{sub 2}{sup +} by circularly polarized ultraviolet laser pulses
Abstract
We study effects of pulse durations on molecular photoelectron angular distributions (MPADs) in ultrafast circular polarization ultraviolet resonant ionization processes. Simulations performed on aligned H{sub 2}{sup +} by numerically solving time dependent Schrödinger equations show rotations of MPADs with respect to the molecular symmetry axes. It is found that in multiphoton resonant ionization processes, rotation angles are sensitive to pulse durations, which we attribute to the coherent resonant excitation between the ground state and the intermediate excited electronic state induced by Rabi oscillations. Multiphoton nonresonant and single photon ionization processes are simulated and compared which exhibit a constant rotation angle. An asymmetry parameter is introduced to describe the pulse duration sensitivity by perturbation theory models. Influence of pulse frequency detunings on MPADs is also investigated where oscillations of rotations are absent at long pulse durations due to nonresonance excitation.
 Authors:
 Laboratoire de Chimie Théorique, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1 (Canada)
 Publication Date:
 OSTI Identifier:
 22415636
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 14; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; ANGULAR DISTRIBUTION; ASYMMETRY; COMPARATIVE EVALUATIONS; EXCITATION; GROUND STATES; HYDROGEN IONS 2 PLUS; MULTIPHOTON PROCESSES; OSCILLATIONS; PERTURBATION THEORY; PHOTOIONIZATION; POLARIZATION; SCHROEDINGER EQUATION; TIME DEPENDENCE; ULTRAVIOLET RADIATION
Citation Formats
Yuan, KaiJun, Email: kaijun.yuan@usherbrooke.ca, Chelkowski, Szczepan, and Bandrauk, André D., Email: andre.bandrauk@usherbrooke.ca. Molecular photoelectron angular distribution rotations in multiphoton resonant ionization of H{sub 2}{sup +} by circularly polarized ultraviolet laser pulses. United States: N. p., 2015.
Web. doi:10.1063/1.4917419.
Yuan, KaiJun, Email: kaijun.yuan@usherbrooke.ca, Chelkowski, Szczepan, & Bandrauk, André D., Email: andre.bandrauk@usherbrooke.ca. Molecular photoelectron angular distribution rotations in multiphoton resonant ionization of H{sub 2}{sup +} by circularly polarized ultraviolet laser pulses. United States. doi:10.1063/1.4917419.
Yuan, KaiJun, Email: kaijun.yuan@usherbrooke.ca, Chelkowski, Szczepan, and Bandrauk, André D., Email: andre.bandrauk@usherbrooke.ca. Tue .
"Molecular photoelectron angular distribution rotations in multiphoton resonant ionization of H{sub 2}{sup +} by circularly polarized ultraviolet laser pulses". United States.
doi:10.1063/1.4917419.
@article{osti_22415636,
title = {Molecular photoelectron angular distribution rotations in multiphoton resonant ionization of H{sub 2}{sup +} by circularly polarized ultraviolet laser pulses},
author = {Yuan, KaiJun, Email: kaijun.yuan@usherbrooke.ca and Chelkowski, Szczepan and Bandrauk, André D., Email: andre.bandrauk@usherbrooke.ca},
abstractNote = {We study effects of pulse durations on molecular photoelectron angular distributions (MPADs) in ultrafast circular polarization ultraviolet resonant ionization processes. Simulations performed on aligned H{sub 2}{sup +} by numerically solving time dependent Schrödinger equations show rotations of MPADs with respect to the molecular symmetry axes. It is found that in multiphoton resonant ionization processes, rotation angles are sensitive to pulse durations, which we attribute to the coherent resonant excitation between the ground state and the intermediate excited electronic state induced by Rabi oscillations. Multiphoton nonresonant and single photon ionization processes are simulated and compared which exhibit a constant rotation angle. An asymmetry parameter is introduced to describe the pulse duration sensitivity by perturbation theory models. Influence of pulse frequency detunings on MPADs is also investigated where oscillations of rotations are absent at long pulse durations due to nonresonance excitation.},
doi = {10.1063/1.4917419},
journal = {Journal of Chemical Physics},
number = 14,
volume = 142,
place = {United States},
year = {Tue Apr 14 00:00:00 EDT 2015},
month = {Tue Apr 14 00:00:00 EDT 2015}
}

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