VH-NG-1105
Programmorientierte Förderung von DESY
VH-NG-1105
Deutsches Elektronen-Synchrotron DESY
Notkestraße 85
22607 Hamburg
Universität Hamburg
Luruper Chaussee 149
22761 Hamburg
Functionality of materials is a result of a particular reaction to external stimuli. Most generally, the excitation spectrum contains all the information about the material: e.g. the absence of excitations in the optical regime and below leads to an optically transparent, insulating material. The existence of a superconducting gap in the excitation spectrum yields the ability to transport electric currents without losses.
Soft X-ray spectroscopies address the excitation spectrum of materials with sensitivity to surfaces and interfaces, selecting signals from the active chemical elements in a compound with specificity to order and symmetries, addressing occupied and unoccupied electronic states. Unfortunately, this powerful information is often accompanied with limited signal levels and sample damage under strong X-ray irradiation needs to be accounted for.
Here, it is proposed to develop novel techniques that fully use coherences in the sample and in optical and X-ray laser beams. Using the unique beam quality produced by X-ray free- electron lasers will allow to study materials with orders of magnitude stronger signals, thus allowing for a reduction of measurement times and exposure to radiation. Alternatively, a much larger parameter space can be sampled, e.g. enabling studies of ultrafast dynamics on the relevant femtosecond timescale. A suite of methods is proposed, transferring concepts from optical laser spectroscopy to the X-ray world. Fully using the coherence in a free- electron laser X-ray beam promises to have an impact similar to the step to lasers in optical spectroscopy.
In order to develop this methodology and to apply it to further our understanding and ability to tailor functional materials, a program with three work packages is proposed. The final experimental realization and application to e.g. manganite systems is preceded by the development of an appropriate, flexible instrument and the identification of optimal experimental parameters through a complete modeling of the underlying processes.
Leader of the Helmholtz Young Investigators Group:
Dr. Martin Beye
DESY
Notkestr. 85
22607 Hamburg
Office:
Phone: +49 40 8998-
Email: martin.beye@desy.de
Partner universitiy:
DESY Photon Science,
Department Physik and
Center for Free-Electron Laser Science
Universität Hamburg
Luruper Chaussee 149
22761 Hamburg
Deutschland
Tel.: +49 40 8998 3706/2129
E-Mail: wilfried.wurth@desy.de
