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Full-Text Articles in Physics
Eikonal Perturbation Theory In Photoionization, F. Cajiao Vélez, Katarzyna Krajewska, J. Z. Kamiński
Eikonal Perturbation Theory In Photoionization, F. Cajiao Vélez, Katarzyna Krajewska, J. Z. Kamiński
Department of Physics and Astronomy: Faculty Publications
The eikonal perturbation theory is formulated and applied to photoionization by strong laser pulses. A special emphasis is put on the first order approximation with respect to the binding potential, which is known as the generalized eikonal approximation [2015 Phys. Rev. A 91 053417]. The ordinary eikonal approximation and its domain of applicability is derived from the generalized eikonal approximation. While the former approach is singular for the electron trajectories which return to the potential center, the generalized eikonal avoids this problem. This property makes it a promising tool for further investigations of rescattering and high-order harmonic generation processes.
Variational Formulation Of Macro-Particle Plasma Simulation Algorithms, Bradley Allan Shadwick, Alexander B. Stamm, Evstati Georgiev Evstatiev
Variational Formulation Of Macro-Particle Plasma Simulation Algorithms, Bradley Allan Shadwick, Alexander B. Stamm, Evstati Georgiev Evstatiev
Department of Physics and Astronomy: Faculty Publications
A variation formulation of macro-particle kinetic plasma models is discussed. In the electrostatic case, the use of symplectic integrators is investigated and found to offer advantages over typical generic methods. For the electromagnetic case, gauge invariance and momentum conservation are considered in detail. It is shown that, while the symmetries responsible for these conservation laws are broken in the presence of a spatial grid, the conservation laws hold in an average sense. The requirements for exact invariance are explored and it is shown that one viable option is to represent the potentials with a truncated Fourier basis