Exciting interaction

In the research programme 'Exciting exchange' physicists are trying to manipulate and control the exchange interaction between electrons at extremely short time and length scales. This interaction is one of the strongest in quantum mechanics and is responsible for magnetic ordering. With the fundamental knowledge that this programme should deliver, the researchers ultimately hope to provide the basis for new technologies that not only make use of the charge but in particular the spin of an electron (spintronics).

To achieve this the researchers must bring a magnetic system into a non-equilibrium state with the help of femtosecond laser pulses and nanostructuring. The exchange interaction then becomes a time-dependent unit and theories based on thermodynamics are no longer applicable. This requires the development and use of highly advanced experimental techniques, such as femtosecond laser and X-ray diffraction, as well as the development of new theories and the production of structured metallic preparations with atomic precision.

Programme leader Theo Rasing: "The field of ultrafast magnetic dynamics is currently very 'hot'. The new programme brings the right expertise together which can ensure that will make the fundamental breakthroughs here that are vital for future applications. Examples are the superfast switching of nanometre magnetic bits and the manipulation of topological spin structures with optical or electrical fields."

This programme is a collaboration between:

• Radboud University: Th. Rasing, M.I. Katsnelson, A. Kirilyuk, A. Kimel;
• Eindhoven University of Technology: B. Koopmans, H.J.M. Swagten;
• University of Twente: P.J. Kelly.