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Aufsatz
Femtosecond dynamics of molecules and clusters
(Ed. by Douwe A. Wiersma, 1994)
The real-time dynamics of multiphoton ionization and fragmentation of molecules - Na_2 , Na_3 - and clusters - Na_n, Hg_n - has been studied in molecular beam experiments employing ion and electron spectroscopy together with femtosecond pump-probe techniques. Experiments with Na_2 and Na_3 reveal unexpected features of the dynamics of the absorption of several photons as seen in the one- and three dimensional vibrational wave packet motion in different potential surfaces and in high laser fields. Cluster size dependent ...
Aufsatz
Femtosecond real-time probing of reactions. 13. Multiphoton dynamics of IHgI
(1993)
Real-time studies of the dynamics were performed on the reaction of HgI_2 in a molecular beam. Excitation was by either one or multi pump photons (311 nm), leading to two separate sets of dynamics, each of which could be investigated by a time-delayed probe laser (622 nm) that ionized the parent molecule and the fragments by REMPI processes. These dynamics were distinguished by combining the information from transients taken at each mass (HgI_2, HgI, I_2, Hg, and I) with the results of pump (and probe) power dependence ...
Aufsatz
Femtosecond two-photon ionization spectroscopy of the B state of Na_3 clusters
(1993)
We report time-resolved experiments studying the dynamics of the Na_3 B-X system. Femtosecond pump-probe techniques combined with ion time-of-flight (TOF) and zero kinetic energy (ZEKE) photoelectron spectroscopy allow us to observe the three-dimensional wavepacket motion in the excited Na_3 B state and in the Na_3 X state. The ground state wavepacket is induced by stimulated emission pumping during the pump pulse. The X-state dynamics is dominated by the three vibrational modes of the Na_3. Furthermore we observed ...
Aufsatz
Asymptotic model for shape resonance control of diatomics by intense non-resonant light: universality in the single-channel approximation
(2015)
Non-resonant light interacting with diatomics via the polarizability anisotropy couples different
rotational states and may lead to strong hybridization of the motion. The modification of shape
resonances and low-energy scattering states due to this interaction can be fully captured by an
asymptotic model, based on the long-range properties of the scattering (Crubellier et al 2015 New J.
Phys. 17 045020). Remarkably, the properties of the field-dressed shape resonances in this asymptotic
multi-channel description ...
Aufsatz
Asymptotic model for shape resonance control of diatomics by intense non-resonant light
(2015)
We derive a universal model for atom pairs interacting with non-resonant light via the polarizability
anisotropy, based on the long range properties of the scattering. The corresponding dynamics can be
obtained using a nodal line technique to solve the asymptotic Schrödinger equation. It consists of
imposing physical boundary conditions at long range and vanishing the wavefunction at a position
separating the inner zone and the asymptotic region. We show that nodal lines which depend on the
intensity of the ...
Aufsatz
Femtosecond wavepacket interferometry using the rotational dynamics of a trapped cold molecular ion
(2015)
A Ramsey-type interferometer is suggested, employing a cold trapped ion and two time-delayed offresonant
femtosecond laser pulses. The laser light couples to the molecular polarization anisotropy,
inducing rotational wavepacket dynamics. An interferogram is obtained from the delay dependent
populations of the final field-free rotational states. Current experimental capabilities for cooling and
preparation of the initial state are found to yield an interferogram visibility of more than 80%. The
interferograms can ...
Aufsatz
Double photoionization of argon into the {3s3p^5} {^1P}- and {^3P}-states
(1994)
Double photoionization of argon was studied
by photon induced fluorescence spectroscopy (PIFS). Cross sections for the double photoionization into the {3s3p^5} {^1P}, {^3P} states of Ar^{+ +} are presented for exciting photon energies between threshold and 120 eV. In the threshold range the energy dependencies of these cross sections were determined for the first time. Singlet and triplet states are populated with comparable probabilities at equal excess energies, in contrast to predictions of the extended Wannier ...