Above-threshold ionization and photoelectron spectra in atomic systems driven by strong laser fields

TY - JOUR

T1 - Above-threshold ionization and photoelectron spectra in atomic systems driven by strong laser fields

AU - Suárez, Noslen

AU - Chacón, Alexis

AU - Ciappina, Marcelo F.

AU - Biegert, Jens

AU - Lewenstein, Maciej

N1 - Publisher Copyright: © 2015 American Physical Society.

PY - 2015/12/28

Y1 - 2015/12/28

N2 - Above-threshold ionization (ATI) results from strong-field laser-matter interaction and it is one of the fundamental processes that may be used to extract electron structural and dynamical information about the atomic or molecular target. Moreover, it can also be used to characterize the laser field itself. Here we develop an analytical description of ATI, which extends the theoretical strong-field approximation (SFA), for both the direct and rescattering transition amplitudes in atoms. From a nonlocal, but separable potential, the bound-free dipole and the rescattering transition matrix elements are analytically computed. In comparison with the standard approaches to the ATI process, our analytical derivation of the rescattering matrix elements allows us to study directly how the rescattering process depends on the atomic target and laser-pulse features; we can turn on and off contributions having different physical origins or corresponding to different physical mechanisms. We compare SFA results with the full numerical solutions of the time-dependent Schrödinger equation (TDSE) within the few-cycle pulse regime. Good agreement between our SFA and TDSE model is found for the ATI spectrum. Our model captures also the strong dependence of the photoelectron spectra on the carrier envelope phase of the laser field.

AB - Above-threshold ionization (ATI) results from strong-field laser-matter interaction and it is one of the fundamental processes that may be used to extract electron structural and dynamical information about the atomic or molecular target. Moreover, it can also be used to characterize the laser field itself. Here we develop an analytical description of ATI, which extends the theoretical strong-field approximation (SFA), for both the direct and rescattering transition amplitudes in atoms. From a nonlocal, but separable potential, the bound-free dipole and the rescattering transition matrix elements are analytically computed. In comparison with the standard approaches to the ATI process, our analytical derivation of the rescattering matrix elements allows us to study directly how the rescattering process depends on the atomic target and laser-pulse features; we can turn on and off contributions having different physical origins or corresponding to different physical mechanisms. We compare SFA results with the full numerical solutions of the time-dependent Schrödinger equation (TDSE) within the few-cycle pulse regime. Good agreement between our SFA and TDSE model is found for the ATI spectrum. Our model captures also the strong dependence of the photoelectron spectra on the carrier envelope phase of the laser field.

UR - http://www.scopus.com/inward/record.url?scp=84953225170&partnerID=8YFLogxK

U2 - 10.1103/PhysRevA.92.063421

DO - 10.1103/PhysRevA.92.063421

M3 - 文章

AN - SCOPUS:84953225170

SN - 1050-2947

VL - 92

JO - Physical Review A - Atomic, Molecular, and Optical Physics

JF - Physical Review A - Atomic, Molecular, and Optical Physics

IS - 6

M1 - 063421

ER -