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
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