Non-Sequential Double Ionization of Ne in Intense Laser Pulses: A Coincidence Experiment

The dynamics of Neon double ionization by 25 fs, 1.0 PW/cm2 laser pulses at 795 nm has been studied in a many particle coincidence experiment. The momentum vectors of all ejected atomic fragments (electrons and ions) have been measured using combined electron and recoil-ion momentum spectroscopy. Electron emission spectra for double and single ionization will be discussed. In both processes the mean electron energies differ considerably and high energetic electrons with energies of more than 120 eV have been observed for double ionization. The experimental results are in qualitative agreement with the rescattering model

Separation of Recollision Mechanisms in Nonsequential Strong Field Double Ionization of Ar: The Role of Excitation Tunneling

Vector momentum distributions of two electrons created in double ionization of Ar by 25 fs, 0.25PW/cm2 laser pulses at 795 nm have been measured using a “reaction microscope.” At this intensity, where nonsequential ionization dominates, distinct correlation patterns are observed in the two-electron momentum distributions. A kinematical analysis of these spectra within the classical “recollision model” revealed an (e,2e)-like process and excitation with subsequent tunneling of the second electron as two different ionization mechanisms. This allows a qualitative separation of the two mechanisms demonstrating that excitation-tunneling is the dominant contribution to the total double ionization yield

Correlated Two-Electron Dynamics in Strong-Field Double Ionization

Vector momenta of electrons and ions have been measured for strong-field (25 fs, 0.25 to 1.0 PW/cm 2) double ionization of Ar using a “reaction microscope.” Correlated two-electron momentum distributions along the field direction (P 1||, P 2||) are explored at different transverse momenta P1⊥ of one of the electrons. Whereas a distinct (P 1||, P 2||) correlation, strongly varying with P1⊥ is observed for nonsequential double ionization at small light intensity, only a weak, but still significant correlation is found at large intensity where sequential ionization dominates

Non-Sequential Double Ionization of Ne in Intense Laser Pulses: A coincidence Experiment

The dynamics of Neon double ionization by 25 fs, 1.0 PW/cm 2 laser pulses at 795 nm has been studied in a many particle coincidence experiment. The momentum vectors of all ejected atomic fragments (electrons and ions) have been measured using combined electron and recoil-ion momentum spectroscopy. Electron emission spectra for double and single ionization will be discussed. In both processes the mean electron energies differ considerably and high energetic electrons with energies of more than 120 eV have been observed for double ionization. The experimental results are in qualitative agreement with the rescattering model

La sclérose combinée de la moelle (à propos de six observations)

MONTPELLIER-BU Médecine UPM (341722108) / SudocPARIS-BIUM (751062103) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF

Coincident fragment detection in strong field photoionization and dissociation of H-2

Electron-ion momentum spectroscopy is used to investigate the correlated electronic and nuclear motion in fragmentation of H- 2 in 4x10(14) W/cm (2) , 25 fs laser pulses at 795 nm. Reaction channel dependent photoelectron spectra indicate that besides the main, stepwise H-2 ionization H-2(+) dissociation mechanism resulting in the products H(1s)+ H++e(-) a second new mechanism has to be assumed. The momentum distribution of H+ ions in the dissociation channels H(1s)+ H++e(-) and 2H(+)+2e (-) is found to be independent of the kinetic energy of the photoelectrons