High-resolution Experiments On Strong-field Ionization Of Atoms And Molecules: Test Of Tunneling Theory, The Role Of Doubly Excited States, And Channel-selective Electron Spectra (springer Theses)
by Lutz Fechner /
2016 / English / PDF
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In this thesis, the ionization of atoms and small molecules in
strong laser fields is experimentally studied using a reaction
microscope. The population of autoionizing doubly excited states
in the laser fields is proven and a possible connection to the
well-known dielectronic recombination processes is discussed.
In this thesis, the ionization of atoms and small molecules in
strong laser fields is experimentally studied using a reaction
microscope. The population of autoionizing doubly excited states
in the laser fields is proven and a possible connection to the
well-known dielectronic recombination processes is discussed.
The fundamental process of tunnel ionization in strong laser
fields is subject of investigation in a pump-probe experiment
with ultrashort laser pulses. A coherent superposition of
electronic states in singly charged argon ions is created within
the first, and subsequently tunnel-ionized with the second pulse.
This gives access to state-selective information about the
tunneling process and allows to test common
models. Moreover, the ionization of krypton and argon at
different wavelengths is studied, from the multiphoton to the
tunneling regime. The wavelength-dependent investigations are
furthermore extended to molecular hydrogen. In addition to
ionization, this system might undergo different dissociative
processes. Channel-selective electron momentum distributions are
presented and compared to each other.
The fundamental process of tunnel ionization in strong laser
fields is subject of investigation in a pump-probe experiment
with ultrashort laser pulses. A coherent superposition of
electronic states in singly charged argon ions is created within
the first, and subsequently tunnel-ionized with the second pulse.
This gives access to state-selective information about the
tunneling process and allows to test common
models. Moreover, the ionization of krypton and argon at
different wavelengths is studied, from the multiphoton to the
tunneling regime. The wavelength-dependent investigations are
furthermore extended to molecular hydrogen. In addition to
ionization, this system might undergo different dissociative
processes. Channel-selective electron momentum distributions are
presented and compared to each other.