Relaxation dynamics of pure and doped He nanodroplets probed by EUV-UV pump-probe ionization at the free-electron laser FERMI

• Applicant: Professor Dr. Marcel Mudrich
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry ; Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2013 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 253772067

The goal of this project is to fully resolve the relaxation dynamics of superfluid helium nanodroplets using EUV-UV pump-probe experiments at the first seeded free-electron laser FERMI@Elettra in Trieste, Italy. This laser is ideally suited owing to its unique features (narrow-band, tunable, ultra-short pulses, synchronization to NIR up to UV laser pulses). Within the approved beamtime, various relaxation channels such as intra- and inter-band vibronic relaxation, dimerization, emission of free Rydberg atoms, autoion-ization, as well as Penning ionization of dopants attached to He droplets will be studied using photoion mass spectrometry and photoelectron imaging detection. The onset of strongly correlated dynamics such as multiple droplet excitation followed by exciton annihilation and collective autoion-ization will be characterized.

• DFG Programme: Research Grants