H2+ ionization by ultra-short electromagnetic pulses investigated through a non-perturbative Coulomb-Volkov approach

V. D. RODRÍGUEZ; P. MACRI; R. GAYET

JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS

Institute of Physics

Lugar: Bristol, United Kingdom; Año: 2005 vol. 38 p. 2775 - 2791

0953-4075

The sudden Coulomb–Volkov theoretical approximation has been shown to well describe atomic ionization by intense and ultra-short electromagnetic pulses, such as pulses generated by very fast highly-charged ions. This approach is extended here to investigate single ionization of homonuclear diatomic molecules by such pulses in the framework of one-active electron. Under particular conditions, a Young-like interference formula can approximately be factored out. Present calculations show interference effects originating from the molecular two-centre structure. Fivefold differential angular distributions of the ejected electron are studied as a function of the molecular orientation and internuclear distance. Both non-perturbative and perturbative regimes are examined. In the non-perturbative case, an interference pattern is visible but a main lobe, opposite to the electric field polarization direction, dominates the angular distribution. In contrast, in perturbation conditions the structure of interferences shows analogies to the Young-like interference pattern obtained in ionization of molecules by fast electron impacts. Finally, the strong dependence of these Young-like angular distributions on the internuclear distance is addressed.