Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Manipulating the texture of magnetism

06.02.2012
Derivation of equations that describe the dynamics of complex magnetic quasi-particles may aid the design of novel electronic devices
Knowing how to control the combined magnetic properties of interacting electrons will provide the basis to develop an important tool for advancing spintronics: a technology that aims to harness these properties for computation and communication. As a crucial first step, Naoto Nagaosa from the RIKEN Advanced Science Institute, Wako, and his colleagues have derived the equations that govern the motion of these magnetic quasi-particles1.

The magnetic behavior of a material is a result of a phenomenon known as spin. This can be thought of as the rotation of electrons and is usually visualized as an arrow pointing along the rotation axis. In some crystalline solids, neighboring electron spins can interact with each other such that the arrows form vortex-like patterns (Fig. 1). This spin ‘texture’ is robust and remains intact despite outside influences; it can also move through the material crystal, even though the atoms themselves remain stationary. Because of these properties, physicists often think of such spin vortices as particles in their own right; they call them skyrmions. The work of Nagaosa, with researchers from China, the Netherlands and Korea, provides a theoretical framework that describes skyrmion dynamics.

Skyrmions, and the ability to control them, have the potential to increase the packing density of magnetic recording media; as such, skyrmion-based devices are likely to be more efficient than conventional memories. “Skyrmions can be moved with a current density as much as a million times smaller than those needed to control magnetic structures, thus far,” explains Nagaosa.

The researchers theoretically investigated skyrmion crystals—ordered arrays of many skyrmions—that are supported by thin metallic films. Nagaosa and his collaborators2 had suggested previously that skyrmion crystals are more stable in thin films than they are in thicker ‘bulk’ materials, making films more amenable to practical applications. The equations of motion derived by Nagaosa and colleagues also showed: how the electrons are influenced by skyrmions; that skyrmions can become pinned to impurities in the film; and that the skyrmion trajectory bends away from the direction of an electrical current. The researchers called this phenomenon the skyrmion Hall effect because of its similarity to the sideways force that is exerted on an electron as it moves through a conductor in a magnetic field, which was discovered by Edwin Hall in 1879.
“Next we intend to study the effect of thermal fluctuations of the skyrmion structure and the optical manipulation of skyrmions,” says Nagaosa. “These are the important issues on the road towards applications.”

The corresponding author for this highlight is based at the Theoretical Design Team, RIKEN Advanced Science Institute

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

More articles from Physics and Astronomy:

nachricht NASA Protects its super heroes from space weather
17.08.2017 | NASA/Johnson Space Center

nachricht New thruster design increases efficiency for future spaceflight
16.08.2017 | American Institute of Physics

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Climate change: In their old age, trees still accumulate large quantities of carbon

17.08.2017 | Earth Sciences

Modern genetic sequencing tools give clearer picture of how corals are related

17.08.2017 | Life Sciences

Superconductivity research reveals potential new state of matter

17.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>