Leading scientists on topological insulators met in Berlin
Outstanding researchers took part in the “New Trends in Topological Insulators 2014” - workshop.
From July 7-10, 150 researchers met in Berlin to discuss recent findings in the field of topological insulators.
Topological insulators are a rather new form of quantum matter with an insulating bulk and a metallic surface created by topologically protected and spin polarized electronic states.
Outstanding researchers took part in the “New Trends in Topological Insulators 2014” - workshop, organized by Gustav Bihlmayer (Forschungszentrum Jülich) and Saskia Fischer (Humboldt University and Oliver Rader of HZB. 20 speakers had been invited for presentations, the 2012 Buckley Prize winners Shoucheng Zhang and Laurens W. Molenkamp (also Leibniz Prize 2014), Zhi-Xun Shen (Buckley prize 2011) and Yoichi Ando (2014 Inoue Prize for Science) being among them.
Breakthrough results were delivered on topics such as optical excitation, electron-photon entangled states, the role of electron correlation as well as imaging of helical edge states and Majorana fermions.
The event took place on the premises of the Berlin-Brandenburg Academy of Sciences. It has been generously supported by DFG as well as HZB.
- Ultrafast dissociation of molecules studied at BESSY IIFor the first time, an international team has tracked at BESSY II how heavy molecules – in this case bromochloromethane – disintegrate into smaller fragments when they absorb X-ray light. Using a newly developed analytical method, they were able to visualise the ultrafast dynamics of this process. In this process, the X-ray photons trigger a "molecular catapult effect": light atomic groups are ejected first, similar to projectiles fired from a catapult, while the heavier atoms - bromine and chlorine - separate more slowly.
- Battery research with the HZB X-ray microscopeNew cathode materials are being developed to further increase the capacity of lithium batteries. Multilayer lithium-rich transition metal oxides (LRTMOs) offer particularly high energy density. However, their capacity decreases with each charging cycle due to structural and chemical changes. Using X-ray methods at BESSY II, teams from several Chinese research institutions have now investigated these changes for the first time with highest precision: at the unique X-ray microscope, they were able to observe morphological and structural developments on the nanometre scale and also clarify chemical changes.
- BESSY II: New procedure for better thermoplasticsBio-based thermoplastics are produced from renewable organic materials and can be recycled after use. Their resilience can be improved by blending bio-based thermoplastics with other thermoplastics. However, the interface between the materials in these blends sometimes requires enhancement to achieve optimal properties. A team from the Eindhoven University of Technology in the Netherlands has now investigated at BESSY II how a new process enables thermoplastic blends with a high interfacial strength to be made from two base materials: Images taken at the new nano station of the IRIS beamline showed that nanocrystalline layers form during the process, which increase material performance.