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Showing 1 to 10 of 10 for “"above-threshold ionization"”.
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A simple model of above threshold ionization
A simple model for above threshold ionization is presented in this work. It is based on modeling the pulsed laser beam involved in ionization as a cylinder consisting of elementary cells whose volumes are very small compared to the pulse volume. A cell is occupied by a number of photons determined …
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Interactions of intense optical and extreme-ultraviolet lasers with atoms and solids
… in this study was the understanding of two-color above-threshold ionization in rare gases. The intense extreme-ultraviolet (EUV) radiation from FLASH was combined with an intense synchronized optical laser (800 nm, 4 ps). The photoelectron spectrum revealed one strong photoline attributed to the …
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Ionization of large molecules with short laser pulses
… observed were shown not to be due to tunneling ionization. The photoelectron distributions showed a prolongation along the laser eld polarization axis, which was interpreted as eld-assisted thermal ionization. For the smallest molecule in the study, anthracene, a transition to atomic like, above …
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Multiphoton ionization photoelectron spectroscopy of iodine-bearing molecules
Multiphoton ionization of iodine-bearing molecules has been studied, under collision-free conditions, by observing the kinetic energy of the ejected photoelectrons. These experiments have demonstrated that, for photoionization of I$\sb2$, CF$\sb3$I and HI at 532 nm, the scission of the R-I bond …
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Atoms in intense ultrashort laser pulses and the absolute phase
… und der Ionisation über Zustände im Kontinuum (``above-threshold ionization'', ATI). Besonders letzterer Effekt wird detailliert in Verbindung mit der Wechselwirkung mit Laserpulsen von nur wenigen Zyklen Länge untersucht. Während es heutzutage Routine ist solche Pulse von weniger als 5 fs zu …
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The Development of a Novel Femtosecond Xuv Light Source to Do Spectroscopy of Atoms and Molecules.
… interaction. As a consequence, Multiphoton Ionization (MPI), Above Threshold Ionization, and High Order Harmonic Generation (HOHG) are the primary phenomena associated with this special interaction. High order harmonic generation (HOHG) is a promising way to generate usable short pulse VUV …
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Semiklassische Dynamik in starken Laserfeldern
Es werden mit einem semiklassischen Propagator in Anfangswertdarstellung <br>Multiphotonprozesse in starken Laserfelden gerechnet. Mit demselben Verfahren <br>wird die semiklassische Propagation eines Wellenpakets im dreidimensionalen <br>Coulomb-Potential untersucht. Mittels der semiklassischen …
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Korrelierte Elektron-Ion-Stöße in starken Laserfeldern
… regime, multi-photon processes, known from the ionization of neutral atoms ( Above-Threshold Ionization), and successive, so called correlated collisions, are important. The subject of the thesis is a study of binary Coulomb collisions in strong laser fields. The collisions are treated both in …
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Experimental examination of ionization processes of noble gases in strong laser fields
… high number of photons available, allows the ionization of noble gas atoms by absorption of a great number of IR-photons, whose individual energy is much smaller than the atom s ionization potential. Alternatively, the interaction may be described in terms of fields: The laser modifies the …
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Untersuchungen der Wellenlängenabhängigkeit von Ionisationsprozessen von Xenon und Krypton in starken ultra-kurzen Laserfeldern
Die Beobachtung dynamischer Vorgänge steht nach wie vor im Mittelpunkt zahlreicher Forschungen auf vielen, <br>nicht nur physikalischen, Arbeitsgebieten. Die Beobachtung der <br>Dynamik eines Prozesses trägt oft wesentlich mehr zum Verständnis <br>der Physik bei als ausschließlich die Messung eines …