ИСТИНА

Light-induced coherent control of the photoelectron angular distribution (PAD) in neon was recently achieved using the Free-Electron Laser (FEL) at FERMI. To gain a better understanding of these processes, which promise a rich field of possibilities in the control of matter, we investigated two-pathway interferences in the ionization of neon induced by the fundamental and second harmonic of a femtosecond XUV pulse when either 2p^5 4s ^1P or 2p^5 3s ^1P are chosen as intermediate states to enhance the two-photon ionization probability. Using a time-dependent approach supported by a perturbative formalism, we analyze the effects of varying the fundamental frequency, intensity ratio between harmonics, and carrier envelope phase. Our results are compared with new experimental data. We also discuss the additional degree of freedom provided by adding an infrared field and comparing the PADs of the sidebands obtained by time-dependent calculations and the strong-field approximation.