Our Research Activities
We study the energy transport and dissipation processes on the nanoscale in metals, dielectrics and heterosystems after strong localized electronic excitations induced by energtic ions. The details of the relevant physical mechanisms depend strongly on the type of ion, its kinetic energy and charge state.
We aim to gain a better understanding of ion-surface interactions using various ion beams provided by accelerator facilities such as GANIL, GSI, RBI and by our own Beamline HICS. The results will help to reveal the fundmental mechanisms of ion-solid interactions and to establish methods for the controlled modification of surfaces and 2D materials by energetic ion irradiation.
Our research is funded by the DFG, the BMBF, the DAAD, and the EU.
The properties of two-dimensional materials differ in many aspects from their bulk counterparts. Therefore, 2D materials are envisaged to play an important role in future electronic devices. The unique electronic properties may however be easily affected by e.g. ambient conditions due to the two-dimensional nature of the corresponding material. We investigate the intrinsic properties of 2D systems such as graphene and single layer MoS2 and study how these can be modified in a controlled way.
To obtain a quantitative characterisation of energy dissipation processes in solids during and after the impact of energetic ions we use two special kinds of ion types:
Swift heavy ions (SHI). This type of beam is generated in large scale accelerators, such as GSI or GANIL. The projectiles trigger an intense electronic excitation along their trajectory, wich may result in permanent modifications, the socalled ion tracks. In a grazing incidence geometry these tracks can be studied at the surface of a material.
Highly charged ions (HCI). These projectiles offer the unique possibility to study both, the effects of kinetic and potential energy on energy dissipation during the ion-solid interaction. The HCI are produced by an Electron Beam Ion Trap (EBIT) at our HICS-setup.