IAFE   05512
INSTITUTO DE ASTRONOMIA Y FISICA DEL ESPACIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Intracycle diffraction in atomic ionization by short-laser pulses: The time grating
Autor/es:
D. G. ARBÓ; K. L. ISHIKAWA; X. XIE; S. ROITHER; M. KITZLER; S. GRÄFE; J. BURGDÖRFER
Lugar:
Aarhus
Reunión:
Conferencia; 11th European Conference on Atoms Molecules, and Photons - ECAMP X; 2013
Institución organizadora:
Organizing commitee
Resumen:
Interference effects observed in the electron yield of atomic ionization due to the interaction with linearly polarized laser pulses are studied. The interplay between intra- and intercycle interferences of electron trajectories leads to modulations in the photoelectron doubly-differential momentum distributions. Intracycle interference comes from the coherent superposition of electron wave packets released within the same optical cycle, whereas Intercycle interference corresponds to the well-known ATI peaks of the photoelectron spectrum arising from the superposition of wave packets of different optical cycles. The former corresponds to a diffraction grating in the time domain. In Fig. 1 we display the doubly differential momentum distribution obtained by using a semiclassical calculation based on the Simple Man’s Model, and computing the time-dependent Schrödinger equation (lower figure). The intercycle interference pattern can be seen as concentric rings, which are modulated by the intracycle interference observed as oblique stripes. The intracycle interference modulation is independent of the number of optical cycles involved in the laser pulse and is affected by the long-range nature of the atomic potential.