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.
- MXene as a frame for 2D water films shows new propertiesAn international team led by Dr. Tristan Petit and Prof. Yury Gogotsi has investigated MXene with confined water and ions at BESSY II. In the MXene samples, a transition between localised ice clusters to quasi-two-dimensional water films was identified by increasing temperature. The team also discovered that the intercalated water structure drives a reversible transition from metallic to semiconducting behaviour of the MXene film. This could enable the development of novel devices or sensors based on MXenes.
- Lithium-sulphur batteries with lean electrolyte: problem areas clarifiedUsing a non-destructive method, a team at HZB investigated practical lithium-sulphur pouch cells with lean electrolyte for the first time. With operando neutron tomography, they could visualise in real-time how the liquid electrolyte distributes and wets the electrodes across multilayers during charging and discharging. These findings offer valuable insights into the cell failure mechanisms and are helpful to design compact Li-S batteries with a high energy density in formats relevant to industrial applications.
- Self assembling monolayer can improve lead-free perovskite solar cells tooTin perovskite solar cells are not only non-toxic, but also potentially more stable than lead-containing perovskite solar cells. However, they are also significantly less efficient. Now, an international team has succeeded in reducing losses in the lower contact layer of tin perovskite solar cells: The scienstists identified chemical compounds that self-assemble into a molecular layer that fits very well with the lattice structure of tin perovskites. On this monolayer, tin perovskite with excellent optoelectronic quality can be grown, which increases the performance of the solar cell.