2020-01-09: New article online in J. Phys. Chem. Letters

We proudly present our publication "Revealing Ultrafast Population Transfer between Nearly Degenerated Electronic States", published in The Journal of Physical Chemistry Letters. The paper originates from a close cooperation of us with the Gonzáles Research Group (University of Vienna), and investigates the fast and complex coupling of different electronic states after acetone photoexcitation. Only the close interplay between experiment and simulation allows to disentangle the mutual couplings underlying the overall ultrafast relaxation.
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2020-01-03: New article online in J. Chem. Phys.

We are happy to present our publication "Ultrafast photoinduced dynamics of single atoms solvated inside helium nanodroplets", published in The Journal of Chemical Physics. In this study, the photoexcitation dynamics of single atoms in helium nanodroplets (as described in Thaler et. al.) is fully characterized and detailed insights into the photoinduced excess energy redistribution as well as the dopant location prior photoexcitation are obtained.
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2019-04-30: New article online in J. Phys. Chem. A.

Our newst publication "Conservation of Hot Thermal Spin-Orbit Population of 2P Atoms in a Cold Quantum Fluid Environment" has gone online in The Journal of Physical Chemistry A. In this work we continue our studies on indium in helium nanodroplets. We find that the spin-orbit split ground states show a strange behaviour of absent relaxation, despite having "temperatures" several orders of magnitude higher than the superfluid surrounding them.
Link to article.


2019-03-18: Prize awarded for ultrafast spectroscopy.

Markus Koch receives the Josef Krainer Würdigungspreis for his work on ultrafast phytodynamics in helium nanodroplets.
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2019-01-19: New article online in 'entropy'

We proudly present the next extension to our Bayesian data analysis approach in the Journal Entropy. The article with the title "Bayesian Analysis of Femtosecond Pump-Probe Photoelectron-Photoion Coincidence Spectra with Fluctuating Laser Intensities" deals with the subtraction of false coincidences of background-rich pump-probe spectra. Additionally, the experimentally always present laser fluctuations are dealt with by inherently incorporating them in the derivation of the Bayesian procedure.
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2018-10-01: New article online in Nature Communications

We are delighted, that our first results regarding ultrafast studies in helium nanodroplets (HeN) have now gone online in Nature Comunications (open access). The results describe the ultrafast processes that are triggered py single-atom photoexcitation of indium inside the droplets. We were able to investigate this solvent response by means of time-resolved photoelectron spectroscopy, supported by time-dependent helium Density Functional Theory simulations. As the droplet reaction on impurity-light-interaction will be similar for the vast variety of possible molecular systems that can be studied inside HeN, our results pave the way to use superfluid helium as a cold container to study ultrafast processes for more complex systems.
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2018-06-08: New article online in Phys. Rev. A.

Our latest publication "Analysis of femtosecond pump-probe photoelectron-photoion coincidence measurements applying Bayesian probability theory" is now online in Physical Review A. In the article we describe a method based on Bayesian-probability approaches, that allow the consistent evaluation of background-subtracted coincidence data in pump-probe studies. Also the algorithm shows how the overall present false coincidences can be properly estimated and subtracted out of the data. The corresponding program codes (Matlab and C++) and a short Manual are available via GitHub.
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2017-07-24: New article online in J. Phys. Chem. A.

Our publication "The Role of Rydberg–Valence Coupling in the Ultrafast Relaxation Dynamics of Acetone" has gone online in Journal of Physical Chemistra A. In the article we continue our studies on molecular relaxation studies on the molecule acetone and analyse the role of an effective coupling between valence and Rydberg states by measuring ultrafast population transfer (~100-200 fs) between the states. It is also the first publication where our newly developed Bayes algorithm is applied to increase the signal/noise ratio of pump-probe coincidence spectra.
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2017-03-31: New article accepted in Journal of Physics B: Atomic, Molecular and Optical Physics 

We are very happy that our publication "Direct observation of a photochemical activation energy: A case study of acetone photodissociation" is now accepted and also available online in Journal of Physics B: Atomic, Molecular and Optical Physics. The paper discusses a single femtosecond pulse study on the dissociation dynamics in acetone and how the energy after photoexcitation is redistributed within a molecule to induce fragmentation.
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2016-09-01: Project launch: Photoinduced Dynamics in a Quantum Fluid Environment

The FWF project "Photoinduced Dynamics in a Quantum Fluid Environment" (P 29369) starts. We will investigate femtosecond dynamics of simple dopants (atoms and molecules) located inside superfluid helium nanodroplets. The dynamics will be initiated by photoexcitation and probed by photoionization and electron/ion detection.


2016-07-26: New article accepted in J. Phys. Chem. A

Our article entitled "Disentangling Multichannel Photodissociation Dynamics in Acetone by Time-Resolved Photoelectron-Photoion Coincidence Spectroscopy" is accepted for publication in The Journal of Physical Chemistry A. This work applies femtosecond photoelectron-photoion coincidence spectroscopy to study relaxation and fragmentation dynamics of highlying Rydberg states in isolated acetone molecules.
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