TY - JOUR

T1 - Modelling laser-atom interactions in the strong field regime

AU - Galstyan, A

AU - Popov, Yu

AU - Mota-Furtado, Francisca

AU - O'Mahony, Patrick

AU - Janssens, N

AU - Jenkins, Samuel

AU - Chuluunbaatar, O

AU - Piraux, Bernard

PY - 2017/4

Y1 - 2017/4

N2 - 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.

AB - 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.

U2 - 10.1140/epjd/e2017-70707-8

DO - 10.1140/epjd/e2017-70707-8

M3 - Article

SN - 1434-6060

VL - 71

SP - 1

EP - 11

JO - European Physical Journal D: Atomic, Molecular, Optical and Plasma Physics

JF - European Physical Journal D: Atomic, Molecular, Optical and Plasma Physics

M1 - 97

ER -