Femtosecond Dynamics - Koch Group

We investigate how light interacts with matter. In particular we are interested in ultrafast processes such as nuclear and electronic dynamics, or the transfer of energy and charges, which we study in real time with femtosecond laser pulses. A repertoire of experimental approaches allows us to observe these primary processes in various different systems under diverse environmental conditions: Form isolated molecules in gas phase, over molecular clusters inside superfluid helium nanodroplets, to nanostructured solids.

Open Positions

Master’s Thesis: Real-Time Investigation of Exciton Dynamics in Molecular Crystals with Ultrafast Microscopy

We are looking for a highly motivated Master student for a thesis at the ultrafast microscope. Together with PhD student DI Robert Schwarzl, the student will investigate the light--matter interaction of squaraine-based molecular crystals. In particular, the so-far unobserved dynamics of Frenkel excitons and charge-transfer excitons  on their intrinsic time- and length scale are of interest. The state-o-the-art setup will achieve (sub-) micrometer spatial and femtosecond temporal resolution.

These technologically important molecular crystals are promising for photovoltaic applications, bio-markers and sensors as they can be efficiently excited in the NIR-VIS spectrum.

Latest News

2021-07-09: Nature Communications paper. First demonstration that electrons in liquids can be accelerated with laser pulses. Nat Commun 12, 4204

2020-12-10: Bernhard Thaler receives the Award of Excellence from the Austrian Ministry of Education, Science and Research for his PhD Thesis on ultrafast dnamics in He droplets – congratulations Bernhard!

2020-05-01: New Project starts. Femtosecond photochemistry in a quantum solvent, funded by the FWF (P33166), sets out to explore the opportunities and limits of femtosecond specroscopy inside He droplets. - See, He drops can pick up money.

2020-03-20: PRL paper
Long-Lived Nuclear Coherences inside Helium Nanodroplets: Our observation of a  nuclear wave packet motion of molecules inside superfluid He nanodroplets is a big step towards ultrafast photochemistry inside these nano-cryo-containers. We discover that the quantum fluid is a great solvent with extremely low influence on the molecule.
Phys Rev Lett 124, 115301 (2020) | full text
Focus stories: APS Physics magazine | AIP Inside Science
Press coverage: | ChemEurope| Chemie.DE | APA | Der Standard | TU Graz

2020-01-10: JPCL paper
Progress in the understanding of energy transfer in a molecule: Through a collaboration with the González group we obtain detailled insight into the population transfer in acetone.
J. Phys. Chem. Lett. 11, 1443  (2020)
press coverage: ChemEuropeChemie.DE | EurekAlert! | ScienceDaily| PhysOrg | Der Standard | Die Presse

All images © TU Graz/Institute of Experimental Physics