Ionization of atoms by few-cycle EUV laser pulses: carrier-envelope phase dependence of the intra-pulse interference effects

摘要

We have investigated the ionization of the H atom by intense few-cycle laserpulses, in particular the intra-pulse interference effects, and theirdependence on the carrier-envelope phase (CEP) of the laser pulse. In the finalmomentum distribution of the continuum electrons the imprint of two types ofintra-pulse interference effects can be observed, namely the temporal andspatial interference. During the spatial interference electronic wave packetsemitted at the same time, but following different paths interfere leading to aninterference pattern measurable in the electron spectra. This can be alsointerpreted as the interference between a direct and a scattered wave, and thespatial interference pattern as the holographic mapping (HM) of the target.This HM pattern is strongly influenced by the carrier-envelope phase throughthe shape of the laser pulse. Here, we have studied how the shape of the HMpattern is modified by the CEP, and we have found an optimal CEP for theobservation of HM.