Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Vortices get organized

28.02.2011
Exotic entities that arrange into a crystalline structure at near room-temperature could lead to a new approach to electronic memory

A crystal consisting not of atoms but exotic swirling magnetic entities, called skyrmions, has been identified at near room-temperature by Yoshinori Tokura of the RIKEN Advanced Science Institute, Wako, and his colleagues from several other institutes in Japan[1].

Previous observations of a skyrmion crystal state, in transition-metal–silicide materials, have been at cryogenic temperatures below 40 kelvin. The existence of skyrmions at room temperature improves the practicality of harnessing their potential for use in novel computer memories.

Skyrmions are formed on some surfaces when the spins of the electrons—think of an arrow about which each electron rotates—collectively arrange such that they wrap around the surface of a sphere (Fig. 1). This pattern spirals in such a way that the spins on the outside point up whereas those at the core point down. This collection of spins can display many properties associated with a single particle. “A skyrmion crystal is the periodic array of these particle-like entities,” explains Tokura.

Earlier neutron-scattering experiments by other researchers identified this unusual effect in both iron–cobalt silicide and manganese silicide. Tokura and his team, however, investigated skyrmions in iron germanium. This alloy has the same cubic atomic crystal structure as iron–cobalt silicide and manganese silicide—the two materials in which skyrmions have been observed at low temperatures; but it remains in the necessary magnetic structure up to a much higher temperature.

Using a transmission electron microscope, the researchers probed the magnetization on the surface of polished layers of the iron–germanium alloy. They found tell-tale signs of skyrmions at temperatures up to 260 kelvin, particularly when they applied a small magnetic field perpendicularly to the surface.

This material also provides an excellent opportunity to investigate the stability of the skyrmion crystal, the team notes. Previous studies focused on very thin layers of material. Tokura and his team investigated the influence of film thickness and found that for thicknesses greater than the distance between skyrmions, about 75 nanometers in this case, the skyrmion crystal state is suppressed and a more conventional ferromagnetic phase starts to dominate.

Skyrmions could play an important role in the development of spintronics—using electron spin to carry information in the same way that electron charge is used in conventional electronics. “Skyrmion crystals could also be applied in memory and logic devices,” says Tokura. The advantage over conventional systems is that control is achieved using electric, rather than magnetic fields, which is known to be more efficient.

The corresponding author for this highlight is based at the Emergent Materials Department, RIKEN Advanced Science Institute

Journal information

[1] Yu, X.Z., Kanazawa, N., Onose, Y., Kimoto, K., Zhang, W.Z., Ishiwata, S., Matsui, Y. & Tokura, Y. Near room-temperature formation of a skyrmion crystal in thin-films of the helimagnet FeGe. Nature Materials 10, 106–109 (2011).

gro-pr | Research asia research news
Further information:
http://www.rikenresearch.riken.jp/eng/research/6527
http://www.researchsea.com

More articles from Materials Sciences:

nachricht Electron tomography technique leads to 3-D reconstructions at the nanoscale
24.05.2018 | The Optical Society

nachricht These could revolutionize the world
24.05.2018 | Vanderbilt University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

Surgery involving ultrasound energy found to treat high blood pressure

24.05.2018 | Medical Engineering

First chip-scale broadband optical system that can sense molecules in the mid-IR

24.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>