Energy efficient LEDs and lasers with Chalcogenide monolayers
2 (orange) on top of MoS2 (blue). The SPEEM-microscopy reveals coupling between both layers and charge transfer. © F. Kronast/HZB
As reported by nanotechweb.org, monolayers of certain chalcogenides might be used to make energy-efficient nano-optoelectronics devices, such as LEDs, lasers, solar cells, and high-electron-mobility transistors. Scientists of the University of California at Berkeley, the Lawrence Berkeley National Lab and the Helmholtz-Zentrum Berlin für Materialien und Energie in Berlin investigated the electronic and optoelectronic properties of a so called heterojunction of WSe2/MoS2.
“At BESSY II we performed local x-ray photoemission spectroscopy at the SPEEM microscope and could observe interlayer coupling and charge transfer in this new type of heterojunction”, Dr. Florian Kronast, HZB, explains. This makes these types of heterojunctions interesting candidates for new devices.
To the article in nanotechweb
The present work is detailed in PNAS doi: 10.1073/pnas.1405435111.
- 3D magnetic field experiment at BESSY II takes spintronics a step further(Fe0.63Ni0.3Pd0.07)3P or FNPP is a magnetic material that exhibits complex magnetic structures even at room temperature. This makes the material of interest for spintronics, a field that could enable data processing with significantly lower energy consumption. One potential application is novel magnetic memory devices. However, generating and modifying the desired structures in a controlled manner remains a challenge to date. A new study led by HZB has now taken a step forward in this regard. They demonstrated at the worldwide unique VEKMAG-Station at BESSY II, that a tiny external B-field in the plane of the magnetic patterns is sufficient to change them.
- Confirmed figures for the first time: Investments in BESSY are worthwhile for Berlin and GermanyAn impact analysis by DIW Econ demonstrates the scientific and economic value of BESSY II. Every euro invested yields three euros for Germany and as much as ten euros for the State of Berlin. Furthermore, the study provides an economic forecast for the construction of BESSY III.
The impact analysis was presented on 3 September 2026 to Dr Henry Marx, State Secretary for Science and Research in the Berlin Senate. He supports the investment and is a strong advocate for BESSY III. - Detailed insights at BESSY II into the oxidation processes of copperBefore pure copper oxide builds up, complex superstructures such as ‘29’CuxO, are formed. The new results on the '29' CuxO superstructure have relevance for catalyst research and corrosion protection in the development of safe copper containers for nuclear waste repositories.