Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

X-ray photoelectron spectroscopy under real ambient pressure conditions June 28th, 2017

Nanometrics to Participate in the 9th Annual CEO Investor Summit 2017: Accredited investor and publishing research analyst event held concurrently with SEMICON West and Intersolar 2017 in San Francisco June 27th, 2017

NMRC, University of Nottingham chooses the Quorum Q150 coater for its reliable and reproducible film thickness when coating samples with iridium June 27th, 2017

Picosun’s ALD solutions enable novel high-speed memories June 27th, 2017

Spintronics

Smart multi-layered magnetic material acts as an electric switch: New study reveals characteristic of islands of magnetic metals between vacuum gaps, displaying tunnelling electric current March 1st, 2017

First experimental proof of a 70 year old physics theory: First observation of magnetic phase transition in 2-D materials, as predicted by the Nobel winner Onsager in 1943 January 6th, 2017

Investigations of the skyrmion Hall effect reveal surprising results: One step further towards the application of skyrmions in spintronic devices December 28th, 2016

Electron highway inside crystal December 12th, 2016

Chip Technology

Nanometrics to Participate in the 9th Annual CEO Investor Summit 2017: Accredited investor and publishing research analyst event held concurrently with SEMICON West and Intersolar 2017 in San Francisco June 27th, 2017

New TriboLab CMP Provides Cost-Effective Characterization of Chemical Mechanical Wafer Polishing Processes: Bruker Updates Industry-Standard CP-4 Platform for Most Flexible and Reliable Testing June 27th, 2017

Atomic imperfections move quantum communication network closer to reality June 25th, 2017

Research accelerates quest for quicker, longer-lasting electronics: UC Riverside-led research makes topological insulators magnetic well above room temperatures June 25th, 2017

Memory Technology

Picosun’s ALD solutions enable novel high-speed memories June 27th, 2017

New prospects for universal memory -- high speed of RAM and the capacity of flash: Thin films created at MIPT could be the basis for future development of ReRAM June 17th, 2017

Geoffrey Beach: Drawn to explore magnetism: Materials researcher is working on the magnetic memory of the future April 25th, 2017

New ultrafast flexible and transparent memory devices could herald new era of electronics April 1st, 2017

Discoveries

X-ray photoelectron spectroscopy under real ambient pressure conditions June 28th, 2017

Physicists make quantum leap in understanding life's nanoscale machinery June 27th, 2017

Picosun’s ALD solutions enable novel high-speed memories June 27th, 2017

Atomic imperfections move quantum communication network closer to reality June 25th, 2017

Announcements

X-ray photoelectron spectroscopy under real ambient pressure conditions June 28th, 2017

Nanometrics to Participate in the 9th Annual CEO Investor Summit 2017: Accredited investor and publishing research analyst event held concurrently with SEMICON West and Intersolar 2017 in San Francisco June 27th, 2017

NMRC, University of Nottingham chooses the Quorum Q150 coater for its reliable and reproducible film thickness when coating samples with iridium June 27th, 2017

Picosun’s ALD solutions enable novel high-speed memories June 27th, 2017

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