Attosecond charge dynamics in molecules and more complex systems

Domain topic

Laser Physics & Atomic and Molecular Physics

Supervisors

Motivation

The emergence of attosecond light sources (1 as = 10-18 s) has opened up an exciting area of physics giving access to the electron dynamics in matter and allowing the ultrafast electronic and structural processes to be monitored in real-time. This has considerably evolved the understanding of fundamental energy transfer and conversion mechanisms as well as radiation damage effects in (bio)molecules at the atomic scale. However, the very details of the temporal and structural evolution in more realistic systems, such as solvated molecules, remains essentially unexplored with many open questions, such as:

  • How does solvation change the physical and chemical properties of a molecule?

  • What is the role of coupled electron and nuclear dynamics in the molecular functionality in water?

In this project, these and other related questions will be addressed through a bottom-up approach from the actual building blocks to the macromolecules.

Project Description

We will extend the application of attosecond technologies to more realistic species such as micro-solvated molecules. For this, we will use two different attosecond beamlines:

  • The FS-ATTO beamline in Hamburg combines sub-4 fs IR or sub-2 fs UV pulses with attosecond XUV/soft- X ray pulses. XUV attosecond pump pulses can be used to suddenly ionize a molecule, activating electronic oscillations between different molecular sites which are later studied by an ultrashort IR probe field. Alternatively, ultrashort UV pulses can be used to excite neutral molecules, probing the activated electron dynamics with attosecond XUV pulses.

  • The high-intensity XUV beamline in Lund allows for the generation and focusing of attosecond pulses to intensities that are sufficiently high to induce nonlinear processes in the XUV photon energy regime. Using these pulses in combination with a recently designed and commissioned split-and-delay unit, we shall be able to carry out XUV-XUV pump probe experiments, where both pump and probe pulses have durations in the attosecond regime.

Methodological keywords

Ultrafast lasers, control and sync, advanced electronics