International conference QENS 2016 and Workshop WINS 2016 in Potsdam
Participants of QENS 2016 and WINS 2016
From 5th to 9th of September HZB has hosted two international scientific events dedicated to the study of the dynamics at nanoscale, QENS and WINS 2016. While Quasielastic Neutron scattering conference (QENS 2016) was dedicated to the scientific applications, international Workshop on Inelastic spectrometers WINS 2016 allowed to touch on the instrumental aspects. 108 scientists from all over the world participated in these events organized in the heart of the Potsdam.
For the first time in the history of QENS the conference was focused on the exploration of materials for energy and information technology applications. Modeling, either to deeper understanding of experimental data, or in the prediction of new materials and phenomena was integral part of the programme. A special session will be dedicated to water. “Very nice program, perfect organization and all this in such a nice place!” summarized Jean-Marc Zanotti from Saclay, France.
- Magnetic imaging: Micro-flowers increase the local magnetic fieldMaterials with magnetic nanostructures have many potential applications such as in spintronics. To explore such materials, nanoscale magnetic-sensitive imaging techniques are very useful, but up to now only weak magnetic fields could be applied during the imaging process. Now an international collaboration led by Dr. Sergio Valencia, HZB, has developed an approach that overcomes this limitation. The team designed tiny magnetic flux concentrators (MFCs), into which the sample is placed. The geometry of the MFCs resembles a flower with a number of petals which focus the applied magnetic field into its center. This greatly expands the magnetic field range available during imaging, and so the range of magnetic systems that can be investigated. The micro-flowers, enhancing magnetic fields locally, can find application in different nanometric magnetic microscopy techniques.
- Disorder creates new properties in compound semiconductorsAn international research team has demonstrated that the intrinsic disorder of the compound semiconductor CuInSnS₄ can be exploited to influence its optical properties. While the atomic vibrations also sense the local disorder, their response is averaged over many different local environments and therefore appear isotropic, as expected for a cubic crystal. In contrast, the optical excitations, known as excitons, are much more sensitive to the local arrangement of atoms. Surprisingly, they show a direction-dependent optical response even though the average crystal structure is cubic. These findings shed new light on the relationship between disorder and material properties, opening up new options for targeted 'disorder engineering' in optoelectronic and photocatalytic devices.
- Superconducting TES array X-ray spectrometer goes into operation at BESSY IIEurope's first and only TES-spectrometer at a synchrotron source is now in operation at BESSY II, developed within a collaboration between the HZB, the MPI-CEC (Mühlheim-an-der-Ruhr, Germany) and the NIST (Boulder CO, USA). The photon detection efficiency of the new instrument exceeds that of wavelength-dispersive X-ray emission spectrometers by a factor of 100 to 1000. It will be used to investigate the electronic properties of atomically thin layers, nanostructures and highly diluted atomic and molecular samples. The team is looking forward to receiving exciting research proposals from the user community.