Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Spin currents: pure and clean: Switching the orientation of magnetization in a thin metallic film can be achieved using the diffusion of electron spin

Figure 1: Top view of the device used to switch magnetization using a pure spin current. A current, I, is injected from the gold wire into the permalloy film with magnetization M1. The copper wire creates a spin accumulation at the junction (green). The spin diffuses towards the second junction and can switch the magnetization M2 of the second permalloy film. 

Reproduced from Ref. 1 © 2008 Macmillan Publishers Limited
Figure 1: Top view of the device used to switch magnetization using a pure spin current. A current, I, is injected from the gold wire into the permalloy film with magnetization M1. The copper wire creates a spin accumulation at the junction (green). The spin diffuses towards the second junction and can switch the magnetization M2 of the second permalloy film.
Reproduced from Ref. 1 © 2008 Macmillan Publishers Limited

Abstract:
A team of scientists in Japan has demonstrated the possibility of switching the magnetization of a thin magnetic film with a non-conventional and innovative method, achieving a considerable step forward in magnetic data storage and the field known as spintronics.

Spin currents: pure and clean: Switching the orientation of magnetization in a thin metallic film can be achieved using the diffusion of electron spin

Japan | Posted on February 12th, 2009

In magnetic memory devices, information is stored in magnetic elements and typically retrieved by applying a small, external magnetic field. More convenient, however, is the use of a spin-polarized current, in which moving electrons exert a torque on a magnetic element and can switch the direction of its magnetization.

Unfortunately, moving electrons can give rise to electrical noise, which reduces the efficiency of the magnetization control. Now, Yoshichika Otani from the RIKEN Advanced Science Institute in Wako and colleagues have overcome this problem by using a pure spin current1, that is, a diffusion of electron spins without charge motion.

A spin current can be created by the process known as non-local injection: a current is injected into a junction between a metal and a magnetic layer (Fig. 1). When the magnetic element is magnetized, such as a metallic film, electron spins accumulate at the junction, and then diffuse away from the junction to re-equilibrate the spin population in the film. The trick is to then use this spin current to influence the magnetization of another magnetic element placed far from the accumulation point.

Previous attempts to create a pure spin current in this way have all met with limited success. Otani and co-workers therefore focused on optimizing the quality of the interface. In particular, they grew all the layers of their devices in sequence in a single high-vacuum chamber. This prevented possible contamination that could occur while moving a structure between growing chambers.

By examining the electronic transport properties of their device, the researchers were able to demonstrate that when the current injected into the first junction is high enough, it creates a spin current high enough to reverse the magnetization at the second junction. Most importantly, the magnetization can be reversed back by applying the same amount of current in the opposite direction.

Magnetization control using a pure spin current in this way in the high-quality devices fabricated by the team could lead to the realization of very advanced electronic devices. The team believes, for example, that it will be possible to achieve different types of transistors—which have no analogues in current electronics—based only on electron spin.
Reference

1. Yang, T., Kimura, T. & Otani, Y. Giant spin-accumulation signal and pure spin-current-induced reversible magnetization switching. Nature Physics 4, 851-854 (2008).

The corresponding author for this highlight is based at the RIKEN Quantum Nano-Scale Magnetics Team

####

For more information, please click here

Copyright © Riken

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

article

Related News Press

News and information

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Clues on the path to a new lithium battery technology: Charging produces highly reactive singlet oxygen in lithium air batteries May 5th, 2016

Unique nano-capsules promise the targeted drug delivery: Russian scientists created unique nano-capsules for the targeted drug delivery May 5th, 2016

Molybdenum disulfide holds promise for light absorption: Rice researchers probe light-capturing properties of atomically thin MoS2 May 5th, 2016

Spintronics

Spintronics for future information technologies: Spin currents in topological insulators controlled May 2nd, 2016

Atomic magnets using hydrogen and graphene April 27th, 2016

The light stuff: A brand-new way to produce electron spin currents - Colorado State University physicists are the first to demonstrate using non-polarized light to produce a spin voltage in a metal April 26th, 2016

Scientists push valleytronics 1 step closer to reality: Berkeley Lab and UC Berkeley researchers control a promising new way to encode electrons April 6th, 2016

Chip Technology

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Molybdenum disulfide holds promise for light absorption: Rice researchers probe light-capturing properties of atomically thin MoS2 May 5th, 2016

A compact, efficient single photon source that operates at ambient temperatures on a chip: Highly directional single photon source concept is expected to lead to a significant progress in producing compact, cheap, and efficient sources of quantum information bits for future appls May 3rd, 2016

Spintronics for future information technologies: Spin currents in topological insulators controlled May 2nd, 2016

Memory Technology

Hybrid nanoantennas -- next-generation platform for ultradense data recording April 28th, 2016

Magnetic vortices defy temperature fluctuations: Common magnetic mineral is reliable witness to Earth's history April 19th, 2016

A single-atom magnet breaks new ground for future data storage April 15th, 2016

Ames Laboratory physicists discover new material that may speed computing April 12th, 2016

Discoveries

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Unique nano-capsules promise the targeted drug delivery: Russian scientists created unique nano-capsules for the targeted drug delivery May 5th, 2016

Molybdenum disulfide holds promise for light absorption: Rice researchers probe light-capturing properties of atomically thin MoS2 May 5th, 2016

The intermediates in a chemical reaction photographed 'red-handed' Researchers at the UPV/EHU-University of the Basque Country have for the first time succeeded in imaging all the steps in a complex organic reaction and have resolved the mechanisms that explain it May 4th, 2016

Announcements

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Clues on the path to a new lithium battery technology: Charging produces highly reactive singlet oxygen in lithium air batteries May 5th, 2016

Unique nano-capsules promise the targeted drug delivery: Russian scientists created unique nano-capsules for the targeted drug delivery May 5th, 2016

Molybdenum disulfide holds promise for light absorption: Rice researchers probe light-capturing properties of atomically thin MoS2 May 5th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic