Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > An attractive match: The search for improved ‘multiferroic’ materials may benefit from a new discovery in an iron-based oxide compound

Figure 1: Multiferroic coupling in DyFeO3. In the absence of an external magnetic field, no net electric polarization (yellow areas) occurs: overall the electric polarization averages out. In the presence of a magnetic field H the Fe atoms rearrange their magnetic orientation M, leading to a net electric polarization P.
Figure 1: Multiferroic coupling in DyFeO3. In the absence of an external magnetic field, no net electric polarization (yellow areas) occurs: overall the electric polarization averages out. In the presence of a magnetic field H the Fe atoms rearrange their magnetic orientation M, leading to a net electric polarization P.

Abstract:
Materials known as ‘multiferroics' hold great promise as memory storage devices owing to coupling between their magnetic and electric properties. Alas, in the multiferroic materials known to date, this coupling typically is very weak and limited to low temperatures, hampering their uptake in commercial applications. Now, researchers from the RIKEN Advanced Science Institute, Wako, in collaboration with colleagues from the Japan Science and Technology Agency, the University of Tokyo and Tohoku University, have revealed strong multiferroic coupling in the oxide compound DyFeO3.

An attractive match: The search for improved ‘multiferroic’ materials may benefit from a new discovery in an iron-based oxide compound

Japan | Posted on December 5th, 2008

In multiferroic compounds ferromagnetism is coupled with ferroelectricity, a phenomenon where electric charges are separated in a material, such that an internal electric polarization is created. This coupling can be used for sensing applications, but also has potential in memory devices where data is typically stored as magnetic information and read out electronically.

Recently, some oxides of manganese, iron as well as others have been shown to possess strong coupling, but ferroelectricity in these materials is rather weak and only the electrical polarization can be switched by a magnetic field, and not vice versa—a showstopper for many applications. "Our goal is to find materials that show a full coupling between ferromagnetism and electric polarization, hopefully at room temperature," says Yusuke Tokunaga, outlining the team's research strategy.

As reported in Physical Review Letters1, the researchers have demonstrated that DyFeO3 shows large ferroelectric polarization combined with a strong multiferroic coupling. They found the origin of this behavior is the layered structure alternating between the dysprosium (Dy) and iron (Fe) layers (Fig. 1), where the Fe atoms attract Dy atoms through their antiparallel magnetic orientation. In a zero magnetic field, the antiparallel pairs of Dy and Fe atoms cancel out the overall electric polarization.

Under the influence of a sufficiently strong magnetic field, however, the magnetic orientation of the Fe atoms rearranges slightly, which then leads to an electric polarization. As the electric polarization is a direct consequence of the magnetic structure, the multiferroic coupling is very strong—about two orders of magnitude larger than that of most other multiferroic materials.

Unfortunately, temperatures below -269 °C remain a necessity for the observation of this effect. Furthermore, the magnetic field required for the realignment of the magnetic orientation of the Fe atoms is relatively high. Nevertheless, Tokunaga is convinced that DyFeO3 represents a promising blueprint: "We believe DyFeO3 will serve as a template for materials with a large multiferroic coupling, even at higher temperatures."
Reference

1. Tokunaga, Y., Iguchi, S., Arima, T. & Tokura, Y. Magnetic-field-induced ferroelectric state in DyFeO3. Physical Review Letters 101, 097205 (2008).

The corresponding author for this highlight is based at the RIKEN Exploratory Materials 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

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Aculon Hires New Business Development Director December 19th, 2014

Chip Technology

Instant-start computers possible with new breakthrough December 19th, 2014

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

Pb islands in a sea of graphene magnetise the material of the future December 16th, 2014

Stanford team combines logic, memory to build a 'high-rise' chip: Today circuit cards are laid out like single-story towns; Futuristic architecture builds layers of logic and memory into skyscraper chips that would be smaller, faster, cheaper -- and taller December 15th, 2014

Memory Technology

Instant-start computers possible with new breakthrough December 19th, 2014

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

Stanford team combines logic, memory to build a 'high-rise' chip: Today circuit cards are laid out like single-story towns; Futuristic architecture builds layers of logic and memory into skyscraper chips that would be smaller, faster, cheaper -- and taller December 15th, 2014

Graphene layer reads optical information from nanodiamonds electronically: Possible read head for quantum computers December 1st, 2014

Discoveries

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Iranian Scientists Use Nanotechnology to Increase Power, Energy of Supercapacitors December 18th, 2014

Announcements

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Aculon Hires New Business Development Director December 19th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE