Atomicelectron excitation by a local phase shift of the wave function
Abstract
A very simple analytical model is presented to compute the time evolution of an atomic electron interacting with an ultrastrong highfrequency laser field. The model takes into account the evolution of the electronic wave function in terms of the action and trajectory of a classical electron. It shows the possibility of atomic excitation by a spacedependent shift of the wave function. It is an extension of the wellknown strongfield approximation and the dipole Volkov states to the case of spacedependent fields, in the veryhighfrequency regime. The great advantage of the model lies in its applicability in situations where the dipole approximation does not hold and, therefore, ab initio numerical computation of the timedependent Schrödinger equation would require extremely long run times.
 Publication:

Physical Review A
 Pub Date:
 June 2000
 DOI:
 10.1103/PhysRevA.61.063401
 Bibcode:
 2000PhRvA..61f3401V
 Keywords:

 42.50.Hz;
 32.80.Fb;
 Strongfield excitation of optical transitions in quantum systems;
 multiphoton processes;
 dynamic Stark shift;
 Photoionization of atoms and ions