. | . |
Skyrmions a la carte by Staff Writers Kiel, Germany (SPX) Jun 07, 2016
Magnetic vortices - so-called skyrmions - were predicted theoretically more than 25 years ago, but it has only been possible to observe them experimentally in magnetic materials in recent years. Skyrmions are stable, can have a diameter of just a few nanometres, and can be moved efficiently by electrical currents. Therefore, they are presently being discussed as candidates for high density, energy-saving data storage and processing. However, until very recently, the only materials known to exhibit skyrmions did so at extremely low temperatures. Scientists at Kiel University and the research institute Forschungszentrum Julich have predicted that skyrmions can also be produced for applications at room temperature - and their properties specifically adjusted - when enveloped in magnetic layer structures. Their results have been published in the current issue (3 June, 2016) of the renowned scientific journal "Nature Communications". The team, headed by the physicist Dr. Bertrand Dupe, is sure that each skyrmion could store 1 bit of information. The small size of the vortex allows a very high density to be achieved. In contrast with hard drive disks, which are rotated to enable data to be entered or read out, in the case of skyrmion-based devices the Bits could simply be moved right through the material, similar to how electricity flows through a wire. No mechanical moving parts would be required - only weak electrical currents, which saves energy. In addition, once the computer is switched on, the data is available immediately, as it is stored in non-volatile memory. The envisaged devices required could be manufactured with standard technologies currently used in industry. Skyrmions were first observed experimentally in 2009, in exotic crystals at temperatures close to absolute zero. In the meantime, these unique magnetic structures can also be found on metallic surfaces, as used today in technological applications such as magnetic sensors or the reading heads of hard drives. In order to use skyrmions as a storage medium, it must be possible to manufacture the boundary surfaces on a sufficiently large scale, they must contain enough of the magnetic material, and the magnetic vortex must also occur at room temperature. Suggestions on how to overcome these challenges have been made by the scientists from Kiel University and Forschungszentrum Julich in their currently published study. Here, they show that the magnetic properties of the boundary surfaces can be specifically adjusted by layering different metals very thinly on top of one another. Each of the layers is only a few atoms thick. "By using quantum-mechanical calculations, which were carried out on the supercomputers at Forschungszentrum Julich and the North-German Supercomputing Alliance (HLRN), we were able to investigate a multitude of possible systems," said Professor Stefan Heinze from Kiel University. The multiple repetition of such layers ensures that there is enough magnetic material and that it should also be possible to produce skyrmions at room temperature, Heinze continued. "Our study provides the experimenters with recipes for making skyrmions to order," explained Bertrand Dupe. It has recently been proven that these theoretical recipes from the supercomputers can also be implemented in practice. "The idea of producing skyrmions in layer systems has already been taken up by a number of research groups all over the world. A few months ago, several publications reported the successful experimental observation of skyrmions," said Dr. Gustav Bihlmayer from Forschungszentrum Julich. The theoretical basis for these experiments is provided in their latest publication, continued Bihlmayer. However, there is still a long way to go until the first memory applications based on magnetic skyrmions are produced. The development of prototypes of magnetic data storage is being investigated by the Kiel and Julich scientists in the joint project MAGicSky. The experimental tasks are carried out by colleagues from Germany, France, Great Britain and Switzerland. The research is subsidised by the European Union within the Future Emergent Technologies programme. Research paper: Engineering skyrmions in transition-metal multilayers for spintronics, Bertrand Dupe, Gustav Bihlmayer, Marie Bottcher, Stefan Blugel and Stefan Heinze, Nature Communications, online publication dated 3.6.2016, DOI: 10.1038/ncomms11779
Related Links Forschungszentrum Juelich Computer Chip Architecture, Technology and Manufacture Nano Technology News From SpaceMart.com
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |