Using ultrafast laser light pulses, researchers at Lund University in Sweden have discovered a new way to generate nano-sized magnetic particles. The finding could pave the way for new, more energy-efficient technical components, which could be used in future quantum computers.
Image Credit: Claudio Verdozzi
Magnetic vortices are another name for magnetic skyrmions. Unlike ferromagnetic states, which are found in common magnets like compasses and refrigerator magnets, the skyrmion state is unusual in that the magnetization orientation does not point in the same direction throughout the material, but rather is best described as swirling magnetism.
Skyrmions are of significant interest to both basic research and industry because they can be used to make smaller computer memories. That is, however, easier said than done. Using skyrmions for technical purposes necessitates quick and precise ways of writing, erasing and altering the particles in short time scales, but with high spatial precision.
Claudio Verdozzi of Lund University and Emil Viñas Boström and Angel Rubio of Hamburg's Max Planck Institute for the Structure and Dynamics of Matter have discovered a new strategy in a new study.
In our study, we have theoretically shown how it is possible to meet one of these requirements, that is, how to create magnetic skyrmions in ultra-short time scales using pulses of laser light.
Claudio Verdozzi, Researcher, Physics, Lund University
A microscopic mechanism has been discovered by the research group that discusses an experimental method that has been shown to be helpful in the creation of strange skyrmions. The authors indicated that skyrmions can be created ultra-quickly using femtosecond laser pulses, which are light pulses lasting one-millionth of a billionth of a second.
Our results are of great relevance to creating more energy-efficient technical components. Our study shows that light can be used to manipulate localized magnetic excitations in very short time scales.
Claudio Verdozzi, Researcher, Physics, Lund University
The discovery could lead to a variety of applications, including quantum technology, which uses quantum mechanical properties to solve highly complicated calculations that traditional computers cannot handle. Magnetic excitations like skyrmions and so-called spin waves are also thought to be capable of lowering energy consumption in technological components, thereby assisting in the achievement of future climate goals.
Skyrmions are in focus for both theoretical and experimental research thanks to their technological potential. Also, their exotic magnetic patterns possess a conceptually and mathematically beautiful appeal that makes them very interesting.
Claudio Verdozzi, Researcher, Physics, Lund University
Journal Reference:
Boström, E. V., et al. (2022) Microscopic theory of light-induced ultrafast skyrmion excitation in transition metal films. npj Computational Materials. doi.org/10.1038/s41524-022-00735-5.