Time-resolved spectroscopy of interparticle Coulombic decay processes

Abstract

We report theory for time-resolved spectator resonant Interparticle Coulombic Decay (ICD) processes. Following excitation by a short extreme ultraviolet pulse, the spectrum of the resonant ICD electron develops. Strong-field ionization is imagined to quench the decay at different time delays and to initiate regular ICD.In this latter process, the ICD electron signal can be measured without interference effects. The typical lifetimes of ICD processes allow for the observation of oscillations of the time-and energy-differential ionization probability. We propose to utilize this oscillation to measure lifetimes of electronic decay processes.

Interatomic and Intermolecular Coulombic Decay

“…Common to a number of experiments that were and are being carried out is the use of attosecond photon pulses to initiate processes and probe the response of the electronic charge cloud. In this spirit, a recent suggestion of a time-dependent two-color experiment employs resonant ICD to explore fundamental quantum dynamics . An ultrafast XUV pulse excites an inner-valence state to a resonance, which may decay by resonant ICD.…”

“…In this spirit, a recent suggestion of a time-dependent two-color experiment employs resonant ICD to explore fundamental quantum dynamics. 376 An ultrafast XUV pulse excites an inner-valence state to a resonance, which may decay by resonant ICD. Within the decay time, the excited electron of the neutral resonant state might be ionized with a second, ultrafast IR pulse, which quenches the resonant decay but at the same time enables normal ICD.…”

“…A peculiarity, however, is strong field ionization. To our knowledge, there has been, despite theoretical work on the topic (with respect to loosely bound matter), , no experimental observation of ICD in this research field (see, e.g., refs and for work on argon dimers). The intensity needed to generate states decaying by ICD in loosely bound matter by strong fs-lasers is typically very high.…”

Time-resolved Ultrafast Interatomic Coulombic Decay in Superexcited Sodium-doped Helium Nanodroplets

“…This function results from the convolution of the true signal function with the cross-correlation function and is consistent with a more extensive model for the pump-probe dynamics of ICD processes. 41,45 Figure 4 shows the depletion curve and fit to the same data as displayed in figure 3. The depletion model reproduces the experimental measurements to a large extent.…”

Fano meets nuclei: Configuration interaction theory explicitely including nuclear degrees of freedom

“…For time-resolved spectroscopy of electronic decay processes, most of the developed theory considers atomic systems [30][31][32], for whose description the purely electronic Schrödinger equation suffices. However, for Auger-Meitner processes of molecules, molecules bound to a surface, like in heterogeneous catalysis, or an ICD process, the nuclear degrees of freedom will affect the spectra of the emitted electrons.…”