Phase Dependence of Intense Field Ionization: A Study Using Two Colors

Coherent control of ultrafast optical four-wave mixing with two-colorω−3ωlaser pulses

“…By numerically solving the full Maxwell-Bloch equations beyond the slowly-varying envelope and rotating-wave approximations in the time domain, the nonlinear coupling to the optical field at frequency 5ω is found to depend critically on the initial relative phase φ of the two propagating pulses; the coupling is enhanced when the pulses interfere constructively in the center (φ = 0), while it is nearly suppressed when they are out of phase (φ = π). The tuning of the initial absolute phase of the different frequency components of synchronously propapagating ω-3ω femtosecond pulses can serve as a means to control coherent anti-Stokes Raman (CARS) processes.In recent years, encouraged by the developments in the engineering of intense ultrashort laser fields with a well defined absolute phase [1], studies on the phase control of the interaction of two-color strong ultrashort laser pulses in nonlinear materials have received a great interest [2,3,4,5,6,7]. Phenomena arising from such ultrashort pulse interaction can be of extreme importance in fields as diverse as optoelectronics and materials research, in biological applications such as spectroscopy and microscopy, in high harmonic generation, and in photoionization or molecular dissociation, among others.…”

“…In recent years, encouraged by the developments in the engineering of intense ultrashort laser fields with a well defined absolute phase [1], studies on the phase control of the interaction of two-color strong ultrashort laser pulses in nonlinear materials have received a great interest [2,3,4,5,6,7]. Phenomena arising from such ultrashort pulse interaction can be of extreme importance in fields as diverse as optoelectronics and materials research, in biological applications such as spectroscopy and microscopy, in high harmonic generation, and in photoionization or molecular dissociation, among others.…”

Asymmetry in the Strong-Field Ionization of Rydberg Atoms by Few-Cycle Pulses

“…are mixed and ionization takes place at a frequency of 2! [15,16]. In this Letter we studied the asymmetry phenomena in a quite different setting, the ionization of Rydberg atoms by few-cycle radio-frequency (RF) pulses.…”

Quantum coherent control of the photoelectron angular distribution in bichromatic-field ionization of atomic neon

“…In contrast, mixing states of different parities can only be observed in differential characteristics, such as the photoelectron angular distribution (PAD). Demonstrations of the interference between even-and odd-order processes have been reported previously, including control over the PAD in atomic [22][23][24][25][26] or molecular [27] photoionization processes, over the angular distribution of the products in molecular photodissociation [28], as well as over the direction of electron emission and photocurrents in solids [29][30][31]. The important difference between coherent photoionization of an atom and a molecule is that the latter does not possess spherical symmetry and, consequently, interference of waves with opposite parities may be observed in both angleintegrated parameters (electron or cation yields) and the angular distribution of the reaction products.…”