Helmholtz Investigator Group on magnons
Dr Hebatalla Elnaggar is setting up a new Helmholtz Investigator Group at HZB. At BESSY II, the materials scientist will investigate so-called magnons in magnetic perovskite thin films. Her goal is to create the foundations for a new extremely efficient information technology. © HZB
Dr Hebatalla Elnaggar is setting up a new Helmholtz Investigator Group at HZB. At BESSY II, the materials scientist will investigate so-called magnons in magnetic perovskite thin films. The aim is to lay the foundations for future terahertz magnon technology: magnonic devices operating in the terahertz range could process data using a fraction of the energy required by the most advanced semiconductor devices, and at speeds up to a thousand times faster.
Today's semiconductor technology relies on the transport of electrically charged particles. The densely packed semiconductor devices on microchips generate a lot of unwanted heat, which must be dissipated at great expense. The energy requirements of information technology are immense and increasing steeply.
However, in principle, information could be processed without the transport of electrons. The key to this are magnetic patterns, either the spins of charged particles (spintronics) or spin waves in magnetic materials, known as magnons. Such magnons can propagate through a magnetic medium without moving particles, basically frictionless.
Dr Hebatalla Elnaggar is investigating magnetic thin films with a perovskite structure in which magnons can be detected. The materials scientist earned her doctorate from Utrecht University in the Netherlands and worked as a permanent researcher and head of a working group at Sorbonne University and the CNRS in Paris until recently.
Since october 2025 she has started establishing her own Helmholtz Investigator Group at HZB. “My research goal aligns with HZB's mission to discover new materials and advance technologies for a climate-neutral energy future. Here, I have access to BESSY II and its range of state of the art spectroscopic instruments, clean room facilities, and a high-performance computer cluster,” she says.
Helmholtz Investigator Group: Multi-magnons: A platform for next generation THz magnons
- Spin waves inside a nano-oscillator imaged for the first timeFor the first time, researchers have directly imaged the magnetisation dynamics inside a spin Hall nano-oscillator — a nanoscale device that converts direct current into tunable microwave signals and is a promising building block for energy-efficient wireless communication and brain-inspired computing. A Swedish–German team led by the University of Gothenburg and Helmholtz-Zentrum Berlin (HZB) achieved this using time-resolved scanning transmission X-ray microscopy at the MAXYMUS instrument at BESSY II. The results, now published in Advanced Materials, reveal spin-wave features that had escaped previous, indirect measurement techniques.
- Marcel Risch has been appointed Professor at the Freie Universität BerlinMarcel Risch was appointed to a W2-S professorship in the Department of Physics at Freie Universität Berlin in August 2026. His research group has been transformed into the department 'Mechanisms of Sustainable Electrocatalysis'. Risch investigates the fundamental mechanisms of electrocatalytic reactions and, on this basis, develops knowledge- and data-driven strategies to improve electrocatalysts for the sustainable production of hydrogen, fuels and chemicals.
- BESSY II: High-resolution insights into individual biomolecules and catalystsVery small biological samples and even individual biomolecules can now be examined under near-physiological conditions with high confidence at the BESSY II infrared beamline with a newly validated and improved technique: The nanoscale infrared spectroscopy (s-SNOM) with ultra-thin silicon-based membranes. An international team demonstrated after an initial proof of concept, that high-resolution (a few tens of nanometres) nano-IR measurements reliably match expected far-field IR spectra in an aqueous environment. This methodological advance provides a solid foundation for studying biomaterials or observing catalytic processes in a liquid environment.