Featured Research

from universities, journals, and other organizations

Accelerate data storage by several orders of magnitude? Ultra-fast magnetic reversal observed

Date:
April 19, 2011
Source:
Helmholtz Association of German Research Centres
Summary:
A newly discovered magnetic phenomenon could accelerate data storage by several orders of magnitude. With a constantly growing flood of information, we are being inundated with increasing quantities of data, which we in turn want to process faster than ever. Oddly, the physical limit to the recording speed of magnetic storage media has remained largely unresearched. In experiments performed on a particle accelerator, researchers have now achieved ultrafast magnetic reversal and discovered a surprising phenomenon.

Top, centre: While the magnetization of gadolinium (red arrow) has not yet changed, the magnetization of iron (blue arrow) has already reversed. Large picture: The laser pulse (pink) triggers magnetic reversal, while the X-ray pulse (blue) measures it.
Credit: HZB/Radu

A newly discovered magnetic phenomenon could accelerate data storage by several orders of magnitude.

With a constantly growing flood of information, we are being inundated with increasing quantities of data, which we in turn want to process faster than ever. Oddly, the physical limit to the recording speed of magnetic storage media has remained largely unresearched. In experiments performed on the particle accelerator BESSY II of Helmholtz-Zentrum Berlin, Dutch researchers have now achieved ultrafast magnetic reversal and discovered a surprising phenomenon.

In magnetic memory, data is encoded by reversing the magnetization of tiny points. Such memory works using the so-called magnetic moments of atoms, which can be in either "parallel" or "antiparallel" alignment in the storage medium to represent to "0" and "1."

The alignment is determined by a quantum mechanical effect called "exchange interaction." This is the strongest and therefore the fastest "force" in magnetism. It takes less than a hundred femtoseconds to restore magnetic order if it has been disturbed. One femtosecond is a millionth of a billionth of a second. Ilie Radu and his colleagues have now studied the hitherto unknown behaviour of magnetic alignment before the exchange interaction kicks in. Together with researchers from Berlin and York, they have published their results in Nature.

For their experiment, the researchers needed an ultra-short laser pulse to heat the material and thus induce magnetic reversal. They also needed an equally short X-ray pulse to observe how the magnetization changed. This unique combination of a femtosecond laser and circular polarized, femtosecond X-ray light is available in one place in the world: at the synchrotron radiation source BESSY II in Berlin, Germany.

In their experiment, the scientists studied an alloy of gadolinium, iron and cobalt (GdFeCo), in which the magnetic moments naturally align antiparallel. They fired a laser pulse lasting 60 femtoseconds at the GdFeCo and observed the reversal using the circular-polarized X-ray light, which also allowed them to distinguish the individual elements. What they observed came as a complete surprise: The Fe atoms already reversed their magnetization after 300 femtoseconds while the Gd atoms required five times as long to do so. That means the atoms were all briefly in parallel alignment, making the material strongly magnetized. "This is as strange as finding the north pole of a magnet reversing slower than the south pole," says Ilie Radu.

With their observation, the researchers have not only proven that magnetic reversal can take place in femtosecond timeframes, they have also derived a concrete technical application from it: "Translated to magnetic data storage, this would signify a read/write rate in the terahertz range. That would be around 1000 times faster than present-day commercial computers," says Radu.


Story Source:

The above story is based on materials provided by Helmholtz Association of German Research Centres. Note: Materials may be edited for content and length.


Journal Reference:

  1. I. Radu, K. Vahaplar, C. Stamm, T. Kachel, N. Pontius, H. A. Dürr, T. A. Ostler, J. Barker, R. F. L. Evans, R. W. Chantrell, A. Tsukamoto, A. Itoh, A. Kirilyuk, Th. Rasing, A. V. Kimel. Transient ferromagnetic-like state mediating ultrafast reversal of antiferromagnetically coupled spins. Nature, 2011; DOI: 10.1038/nature09901

Cite This Page:

Helmholtz Association of German Research Centres. "Accelerate data storage by several orders of magnitude? Ultra-fast magnetic reversal observed." ScienceDaily. ScienceDaily, 19 April 2011. <www.sciencedaily.com/releases/2011/04/110413101910.htm>.
Helmholtz Association of German Research Centres. (2011, April 19). Accelerate data storage by several orders of magnitude? Ultra-fast magnetic reversal observed. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2011/04/110413101910.htm
Helmholtz Association of German Research Centres. "Accelerate data storage by several orders of magnitude? Ultra-fast magnetic reversal observed." ScienceDaily. www.sciencedaily.com/releases/2011/04/110413101910.htm (accessed July 25, 2014).

Share This




More Computers & Math News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Mobile App Gives Tour of Battle of Atlanta Sites

Mobile App Gives Tour of Battle of Atlanta Sites

AP (July 25, 2014) — Emory University's Center for Digital Scholarship has launched a self-guided mobile tour app to coincide with the 150th anniversary of the Civil War's Battle of Atlanta. (July 25) Video provided by AP
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) — Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) — Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) — 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:  

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile iPhone Android Web
          Follow Facebook Twitter Google+
          Subscribe RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins