Physicist Professor Jörg Kröger of the TU Ilmenau has been awarded the Thuringian Research Prize 2023 in the category of basic research. With the prize, the Free State of Thuringia honors Kröger's many years of research on the quantum physics of matter. Quantum technologies are about to become key technologies. Mastering them requires an understanding of the underlying principles, as Kröger explores them experimentally in his work. Prof. Jörg Kröger's basic research has the potential for innovative applications in electronics or medicine, among others.
"Quantum physics of matter - fundamental research using scanning probe methods to reveal mechanisms and principles on the atomic scale" - this is the title of Prof. Jörg Kröger's research work, which he has been conducting at the highest level for more than a decade at the TU Ilmenau. In addition to imaging individual atoms, molecules and the wave character of matter, Kröger is actively shaping the quantum cosmos. By manipulating matter atom by atom, the researcher is building nano-laboratories in which he can explore quantum physical mechanisms.
The scanning probe microscopes of the Institute of Physics at TU Ilmenau allow quantum research at the limit of what is currently technically possible. Only with such high-end microscopes can the sensitivity be achieved that Prof. Jörg Kröger needs in order to make the world of quanta visible and thus be able to shape it. To this end, for example, the metallic tips of the microscopes are functionalized with individual molecules so that probes for high-resolution images of single molecules can be realized. Other modifications to the tips enable particularly sensitive probes that use nano-magnetism to construct tiny data storage devices or extremely low-energy information technologies. In this way, Kröger also succeeds in realizing the spectroscopy of quantum excitations, i.e., the transmission of minute energy portions, with high energy resolution. In collaboration with theorists at the Technical University of Denmark, he developed a magnifying glass, so to speak, for quantum excitations: The scientists thus succeeded in observing vibrations of the atoms of a two-dimensional material as clearly as never before.
Basic research of the highest importance
In his tribute, Wolfgang Tiefensee, Thuringia's Minister for Economy, Science and Digital Society, emphasized that Prof. Jörg Kröger's research makes electron waves directly visible by scanning tunneling microscopy: "The tips of the microscopes serve as proven tools for constructing artificial structures - nano-laboratories - atom by atom. This is of paramount importance for fundamental research in physics: The gain in knowledge is maximal on model-like systems, since mechanisms and principles of quantum physics can be derived that also apply to more complex setups. It is even possible to turn the tips into sensitive sensors by attaching individual atoms or molecules. This allows one to study superconductivity through molecular circuits, which will be significant in future computer architectures or neuromorphic circuits." Other experiments aim to prepare microscope probes in such a way that functional molecules for nanomedicine, for example, will become conceivable in the future.
Prof. Jörg Kröger's award-winning research was carried out with the help of a self-made scanning tunneling microscope and an atomic force microscope in laboratories at the Center for Micro- and Nanotechnologies (ZMN) at TU Ilmenau, which were specially vibration-damped and shielded for this purpose. In the ForLab project, which is funded by the German Federal Ministry of Education and Research, Kröger has set up another low-temperature scanning tunneling microscope here, with which he is trying to prove that the supercurrent can be controlled by an elementary magnet. If he is successful, an extremely energy-efficient switch based on superconductivity could be constructed, which could become relevant for novel computer architectures and neuromorphic electronics.
Award and impressions of Prof. Kröger's research
Contact
Prof. Jörg Kröger
Head of the Experimental Physics I / Surface Physics Group