Tiny magnetic vortices enable high-density data storage
Skyrmions, predicted in theory more than 25 years ago and so far only proven in a few materials at very low temperatures, are ideal for data storage: Once brought to life, they are stable and they can be moved by means of electric currents. Each skyrmion can store one bit; and their extremely low spatial extension would translate into high-density storage media. Unlike rotating media such as today’s fixed disks, skyrmion-based storage media will contain no moving parts, because the bits move through the matter like electrons through an electric conductor. Like today’s Flash storage, skyrmions promise non-volatile storage.
A research team around Physicist Bertrant Dupé from the Christian-Albrecht University (CAU) in Kiel predicts that skyrmion-based storage can be implemented using technologies that today are established as industrial standard.
Skyrmions have been observed for the first time in 2009 – in crystals of exotic materials and at temperatures near absolute zero. In the meantime however, these unique magnetic structures have been found at metallic boundary surfaces like those of applications in use today such as magnetic sensors or read/write heads of fixed disks. To implement skyrmion-based storage media at an industrial level, these boundary layers need to be producible in a large scale, possess enough magnetic material, and the magnetic vortices need to occur at room temperature.
The Kiel research team along with researchers from the Jülich Research Center have now submitted a study that suggests possible way to solve these challenges. The study states that the magnetic properties of the boundary layers can be set deliberately by stacking extremely thin layers of different metals. Each one of these layers has a thickness of just a few atomic layers. “Through quantum mechanical calculations performed on the high-performance computing centers of the Forschungszentrum Jülich and the Northern German network of High-performance computers we were able to investigate a high number of possible systems”, says CAU professor Stefan Heinze. To make sure there is enough magnetic material and its possible to create skyrmions that are functioning at room temperature, the scientist have to stack many layers of alternating materials, Heinze explained. He added that though these assumptions are based on the results of high-performance computing, they nevertheless recipes to implement skyrmions “à la carte”. Gustav Bihlmayer from the Jülich research center added that the idea to implement skyrmions by stacking thin layers on top of each other has already been picked up by fellow researchers across the world.
However, it still is probably a long way to go until first skyrmion-based data storage applications will be available. As the next step, the researchers from Kiel and Jülich will start the project MaGicSky, that will take a closer look into the feasibility of the theoretical models out of the computer. Within MaGicSky, scientists from France, Germany, Switzerland and the UK will approach the topic by performing experiments. The European Union is funding the undertaking as part of its Future Emergent Technologies Program.
Magnetic Skyrmions for Future Nanospintronic Devices“ (MAGicSky) website: https://magicsky-fet.eu
Research for energy efficent computer components: https://www.fz-juelich.de/SharedDocs/Meldungen/PGI/PGI-1/DE/2015/2015-11-23-MAGicSky.html