IAFE   05512
INSTITUTO DE ASTRONOMIA Y FISICA DEL ESPACIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A Semiclassical Study of the Holographic Interference in Atomic Photoionization
Autor/es:
S. D. LÓPEZ; D. G. ARBÓ
Reunión:
Simposio; The 5th International Symposium on Intense Short Wavelenght Processes in Atoms and Molecules (ISWAMP); 2019
Resumen:
We show novel results on the interference structure in atomic ionization by near-infraredlasers. A theoretical study of the interference pattern imprinted on the doubly differentialmomentum distribution of the photoelectron due to atomic ionization induced by a short laserpulse is developed from a semiclassical standpoint. We use the semiclassical two-stepmodel of Shvetsov-Shilovski et al.1 to elucidate the nature of the holographic structure. Threedifferent types of trajectories are characterized during the ionization process by a single cyclepulse with three different types of interferences. We show that the holographic interferencearises from the ionization yield only during the first half cycle of the pulse, whereas thecoherent superposition of electron trajectories during the first half cycle and the second halfcycle gives rise to two other kinds of intracycle interference. Although the picture ofinterference of a reference beam and a signal beam is adequate, we show that our results forthe formation of the holographic pattern agree with the glory rescattering theory of Xia et al.2.We probe the two-step semiclassical model by comparing it to the numerical results of thetime dependent Schrödinger equation.We show a successful way of how to scrutinize quantum interferences taking place in thesubfemtosecond domain. We use both quantum and semiclassical models to show that ourresults essentially agree with the results of the glory rescattering trajectories of Xia et al. Weidentify the glory trajectories as the limiting ones between rescattering (nearside) and nonrescattering(farside) trajectories 3. However, the picture of interference of a reference beamand a signal beam still persists. Besides the well-known holographic interference, there aretwo other types of intracycle interferences corresponding to different types of electrontrajectories involved in the process: trajectories that rescatter and that do not. The generalappearances of these types of intracycle interferences differs from the found in the literature(essentially using the strong field approximation) due to our accurate way to include theeffect of the Coulomb potential of the remaining core