Chemical and surface dynamics

When a short laser pulse hits a molecule, it changes its state and emits electrons or scatters photons. Analyzing these signals, the states can be determined and the transition process can be followed.

Excitation of molecules and surfaces with X-rays rather than visible light grants access to strongly bound atomic states. For a molecule, the spectrum of the escaping electrons or photons constitute an "atomic finger print" allowing to quantify its elemental composition and - via observation of "chemical shifts" - even the chemical environment of a particular atom within the molecular scaffold (electron spectroscopy for chemical analysis ESCA). Excitation of a surface with X-rays of defined circular or linear polarization, delivers also magnetic contrast (X-ray magnetic circular / linear dichroism XMCD / XMLD). Using ultrashort pulses X-ray sources these techniques can now be equipped with a temporal resolution that allows to study the dynamics of even the fastest relevant chemical or magnetic processes in real time.

Collaborating institutions and scientific programs:

Hasylab at DESY, Hamburg

Institute for Laser Physics, University of Hamburg

Research Training Program GrK1335 at the University of Hamburg