Modelling laser-atom interactions in the strong field regime

We consider the ionisation of atomic hydrogen by a strong infrared field. We extend and study in more depth an existing semi-analytical model. Starting from the time-dependent Schrödinger equation in momentum space and in the velocity gauge we substitute the kernel of the non-local Coulomb potential by a sum of N separable potentials, each of them supporting one hydrogen bound state. This leads to a set of N coupled one-dimensional linear Volterra integral equations to solve. We analyze the gauge problem for the model, the different ways of generating the separable potentials and establish a clear link with the strong field approximation which turns out to be a limiting case of the present model. We calculate electron energy spectra as well as the time evolution of electron wave packets in momentum space. We compare and discuss the results obtained with the model and with the strong field approximation and examine in this context the role of excited states. Graphical abstract: [Figure not available: see fulltext.]. © 2017, EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.

Authors
Galstyan A.1 , Popov Y.V.2, 3 , Mota-Furtado F.4 , O’Mahony P.F.4 , Janssens N.1 , Jenkins S.D.4 , Chuluunbaatar O. 3, 5 , Piraux B.1
Publisher
Springer New York LLC
Number of issue
4
Language
English
Status
Published
Number
97
Volume
71
Year
2017
Organizations
  • 1 Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain, 2 chemin du cyclotron, Box L7.01.07, Louvain-la-Neuve, 1348, Belgium
  • 2 Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Leninskie Gory 1, Moscow, 119991, Russian Federation
  • 3 Joint Institute for Nuclear Research, Zholio-Kyuri str. 6, Dubna, 141980, Russian Federation
  • 4 Department of Mathematics, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, United Kingdom
  • 5 Peoples’ Friendship University of Russia, Miklukho-Maklaya str. 6, Moscow, 117198, Russian Federation
Date of creation
19.10.2018
Date of change
19.10.2018
Short link
https://repository.rudn.ru/en/records/article/record/5568/