National Synchrotron Light Source Seminar

Tuning the x-ray energy close to an absorption edge can cause resonance effects in the diffracted signal, which are dependent on the properties of the material. The resonance effects are due to an increased sensitivity to small changes in the electron distribution around the atom to the absorption edge of which the energy is tuned to. Since the resonant signal can originate from a variety of influences acting on the atom, the challenge in the experiment is often to disentangle or determine the origin of the resonant signal. This is done by varying parameters like polarization, temperature or applied fields.
The new beamline for Resonant Scattering and Diffraction (RSD), P09 at PETRA III, is designed especially for the investigation multipolar ordering processes like charge, magnetic or orbital order. Two diffractometers are available to conduct experiments using the highly brilliant synchrotron beam available at PETRA III. The polarization of the incident x-ray beam can be varied arbitrarily through x-ray phase-plates and the polarization of the scattered beam is analyzed by a polarization analyzer. Low temperature cryostats and high magnetic fields of up to 14 T combined with variable incident x-ray polarization allow the investigation of the electronic properties of the materials under investigation.