The beamlines of the High Resolution and Resonance Scattering Group cover a wide variety of scientific topics and applications, which range from the investigation of static and dynamical magnetic and electronic properties to vibrational dynamics with energy transfers in the neV to eV and µs to fs regime. Investigations of vibrational dynamics are carried out at beamline ID16 and ID28, measuring phonon dispersion relations. The (partial) phonon density of states is determined at the beamlines ID18 and ID22N. Electronic and geometrical structure is studied by X-ray absorption and emission spectroscopy at ID16 and ID26, where information is also gathered about magnetic properties. Magnetic and electric properties, both static and dynamic, are also actively studied by nuclear resonance techniques developed at ID18 and ID22N.

Development of the beamline instrumentation and sample environment continues alongside the scientific programme. On the machine side this comprises optimised undulators for highest brilliance (1·1020 photons/s·0.1% bw·mm2·mrad2) from three undulators with a 11 mm magnetic gap. On the beamline side, the most important developments were made in crystal optics in collaboration with the Optics Group on high-resolution monochromators, analysers, and advanced focusing schemes. Fast detector systems based on avalanche photo diodes and position sensitive detectors based on multi-element drift diodes are other fields of development and application. Finally, a variety of sample environments has been developed and made available to users, such as furnaces, cryostats, superconducting cryomagnet systems, and high-pressure equipment.

The wide range of applications does not permit a full presentation here. Nonetheless, we will mention some scientific fields that are significant activities for the group. One example is the investigation of surface and interface magnetism such as exchange-coupled spring layered systems as Fe/FePt [1] and coarsening of the domain structure in antiferromagnetic Fe/Cr multilayers [2]. Another emphasis is put on the study of matter under extreme conditions. Here we mention the work on the valence-electron structure of liquid germanium and collective dynamics of liquid water [3]. Furthermore, the elucidation of dynamical properties of disordered systems remains an important field [4,5].

In this chapter we present examples of investigations of strongly correlated electron systems. By exploiting the different techniques at our beamlines we aim to contribute to the understanding of electronic, magnetic and dynamic properties of condensed matter.

[1] R. Röhlsberger et al., Phys.Rev.Lett. 89, 237201 (2002).
[2] D.L. Nagy et al., Phys.Rev.Lett. 88, 157202 (2002).
[3] M. Krisch et al., Phys.Rev.Lett. 89, 125502 (2002).
[4] C.A. Burns et al., Phys.Rev.Lett. 89, 236404 (2002).
[5] T. Scopigno et al., Phys.Rev.Lett. 89, 255506 (2002).