Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Magnetic Vortex Reveals Key to Spintronic Speed Limit: Scientists measured a key effect of electron spin essential to engineering the next generation of high-performing digital devices

This color graphic, seen here above an actual image of the vortex core captured by the transmission electron microscope, shows the trapped spins moving around the permalloy sample, which then generate the conical vortex core rising out of the center.
This color graphic, seen here above an actual image of the vortex core captured by the transmission electron microscope, shows the trapped spins moving around the permalloy sample, which then generate the conical vortex core rising out of the center.

Abstract:
The evolution of digital electronics is a story of miniaturization - each generation of circuitry requires less space and energy to perform the same tasks. But even as high-speed processors move into handheld smart phones, current data storage technology has a functional limit: magnetically stored digital information becomes unstable when too tightly packed. The answer to maintaining the breath-taking pace of our ongoing computer revolution may be the denser, faster, and smarter technology of spintronics.

Magnetic Vortex Reveals Key to Spintronic Speed Limit: Scientists measured a key effect of electron spin essential to engineering the next generation of high-performing digital devices

Upton, NY | Posted on August 28th, 2012

Spintronic devices use electron spin, a subtle quantum characteristic, to write and read information. But to mobilize this emerging technology, scientists must understand exactly how to manipulate spin as a reliable carrier of computer code. Now, scientists at the Department of Energy's (DOE) Brookhaven National Laboratory have precisely measured a key parameter of electron interactions called non-adiabatic spin torque that is essential to the future development of spintronic devices. Not only does this unprecedented precision - the findings to be published in the journal Nature Communications on August 28 - guide the reading and writing of digital information, but it defines the upper limit on processing speed that may underlie a spintronic revolution.

"In the past, no one was able to measure the spin torque accurately enough for detailed comparisons of experiment and mathematical models," said Brookhaven Lab physicist Yimei Zhu. "By precisely imaging the spin orbits with a dedicated transmission electron microscope at Brookhaven, we advanced a truly fundamental understanding that has immediate implications for electronic devices. So this is quite exciting."

Speed Limits

Most prevailing technology fails to take full advantage of the electron, which features intrinsic quantum variables beyond the charge and flow driving electricity. One of these, a parameter known as spin direction, can be strategically manipulated to function as a high-density medium to store and transmit information in spintronics. But as any computer scientist can attest, dense data can mean very little without enough speed to process it efficiently.

"One of the big reasons that people want to understand this non-adiabatic spin torque term, which describes the ability to transfer spin via electrical currents, is that it basically determines how fast spintronic devices can be," said Shawn Pollard, a physics Ph.D. student at Brookhaven Lab and Stony Brook University and the lead author of the paper. "The read and write speed for data is dictated by the size of this number we measured, called beta, which is actually very, very big. That means the technology is potentially very, very fast."

Building a Vortex

Consider the behavior of coffee stirred rapidly in a mug: the motion of a spoon causes the liquid to spin, rising along the edges and spiraling low in the center. Because the coffee can't escape through the mug's porcelain walls, the trapped energy generates the cone-like vortex in the center. A similar phenomenon can be produced on magnetic materials to reveal fundamental quantum measurements.

The Brookhaven physicists applied a range of high-frequency electric currents to a patterned film called permalloy, useful for its high magnetic permeability. This material, 50 nanometers (billionths of a meter) thick and composed of nickel and iron, was designed to strictly contain any generated magnetic field. Unable to escape, trapped electron spins combine and spiral within the permalloy, building into an observable and testable phenomenon called a magnetic vortex core.

"The vortex core motion is actually the cumulative effect of three distinct energies: the magnetic field induced by the current, and the adiabatic and non-adiabatic spin torques generated by electrons," Zhu said. "By capturing images of this micrometer (millionth of a meter) effect, we can deduce the precise value of the non-adiabatic torque's contribution to the vortex, which plays out on the nanoscale. Other measurements had very high error, but our technique offered the spatial resolution necessary to move past the wide range of previous results."

Disk Density

The high-speed, high-density hard drives in today's computers write information into spinning disks of magnetic materials, using electricity to toggle between magnetic polarity states that correspond to the "1" or "0" of binary computer code. But a number of intrinsic problems emerge with this method of data storage, notably limits to speed because of the spinning disk, which is made less reliable by moving parts, significant heat generation, and the considerable energy needed to write and read information.

Beyond that, magnetic storage suffers from a profound scaling issue. The magnetic fields in these devices exert influence on surrounding space, a so-called fringing field. Without appropriate space between magnetic data bits, this field can corrupt neighboring bits of digital information by inadvertently flipping "1" into "0." This translates to an ultimate limit on scalability, as these data bits need too much room to allow endless increases in data density.

Nanowire Racetracks

One pioneering spintronic prototype is IBM's Racetrack memory, which uses spin-coherent electric current to move magnetic domains, or discrete data bits, along a permalloy wire about 200 nanometers across and 100 nanometers thick. The spin of these magnetic domains is altered as they pass over a read/write head, forming new data patterns that travel back and forth along the nanowire racetrack. This process not only yields the prized stability of flash memory devices, but also offers speed and capacity exceeding disk drives.

"It takes less energy to manipulate spin torque parameters than magnetic fields," said Pollard. "There's less crosstalk between databits, and less heat is generated as information is written and read in spin-based storage devices. We measured a major component critical to unlocking the potential of spintronic technology, and I hope our work offers deeper insight into the fundamental origin of this non-adiabatic term."

The new measurement pins down a fundamental limit on data manipulation speeds, but the task of translating this work into practical limits on processor speed and hard drive space will fall to the scientists and engineers building the next generation of digital devices.

Zhu and Pollard collaborated with two physicists specializing in nanomagnetism, Kristen Buchanan of Colorado State University and Dario Arena of Brookhaven's National Synchrotron Light Source (NSLS), to push the precision capabilities of the transmission electron microscope. This research was conducted at Brookhaven Lab's Department of Condensed Matter Physics and Materials Science, and funded by the U.S. Department of Energy's Office of Science.

DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov .

####

About Brookhaven National Laboratory
One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by the Research Foundation for the State University of New York on behalf of Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

Visit Brookhaven Lab's electronic newsroom for links, news archives, graphics, and more at www.bnl.gov/newsroom, follow Brookhaven Lab on Twitter, twitter.com/BrookhavenLab, or find us on Facebook, www.facebook.com/BrookhavenLab/.

For more information, please click here

Contacts:
Justin Eure
(631) 344-2347

or
Peter Genzer
(631) 344-3174

Copyright © Brookhaven National Laboratory

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 News Press

News and information

Oxford Instruments systems now facilitate water purification technology September 27th, 2016

Dr Barbara Armbruster promoted to Worldwide Sales and Marketing Director for XEI Scientific September 27th, 2016

Fighting cancer with sticky nanoparticles September 27th, 2016

Gold nanoparticles conjugated quercetin inhibits epithelial-mesenchymal transition, angiogenesis and invasiveness via EGFR/VEGFR-2 mediated pathway in breast cancer September 27th, 2016

Laboratories

Crystalline Fault Lines Provide Pathway for Solar Cell Current: New tomographic AFM imaging technique reveals that microstructural defects, generally thought to be detrimental, actually improve conductivity in cadmium telluride solar cells September 26th, 2016

NIST Patents Single-Photon Detector for Potential Encryption and Sensing Apps September 16th, 2016

Electron beam microscope directly writes nanoscale features in liquid with metal ink September 16th, 2016

World's most powerful X-ray takes a 'sledgehammer' to molecules September 14th, 2016

Physics

New breed of optical soliton wave discovered September 9th, 2016

NREL discovery creates future opportunity in quantum computing: Research into perovskites looks beyond material's usage for efficient solar cells September 9th, 2016

Location matters in the self-assembly of nanoclusters: Iowa State University scientists have developed a new formulation to explain an aspect of the self-assembly of nanoclusters on surfaces that has broad applications for nanotechnology September 8th, 2016

University of Akron researchers find thin layers of water can become ice-like at room temperature: Results could lead to an assortment of anti-friction solutions August 30th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Crystalline Fault Lines Provide Pathway for Solar Cell Current: New tomographic AFM imaging technique reveals that microstructural defects, generally thought to be detrimental, actually improve conductivity in cadmium telluride solar cells September 26th, 2016

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

PHENOMEN is a FET-Open Research Project aiming to lay the foundations a new information technology September 19th, 2016

NIST Patents Single-Photon Detector for Potential Encryption and Sensing Apps September 16th, 2016

Spintronics

NREL discovery creates future opportunity in quantum computing: Research into perovskites looks beyond material's usage for efficient solar cells September 9th, 2016

Making the switch, this time with an insulator: Colorado State University physicists, joining the fundamental pursuit of using electron spins to store and manipulate information, have demonstrated a new approach to doing so, which could prove useful in the application of low-powe September 2nd, 2016

NREL Discovery Creates Future Opportunity in Quantum Computing: Research into perovskites looks beyond materialís usage for efficient solar cells September 1st, 2016

Swapping substrates improves edges of graphene nanoribbons: Using inert boron nitride instead of silica creates precise zigzag edges in monolayer graphene August 2nd, 2016

Chip Technology

Researchers at the Catalan Institute of Nanoscience and Nanotechnology show that bending semiconductors generates electricity September 26th, 2016

Mexican scientist in the Netherlands seeks to achieve data transmission ... speed of light September 20th, 2016

Towards Stable Propagation of Light in Nano-Photonic Fibers September 20th, 2016

PHENOMEN is a FET-Open Research Project aiming to lay the foundations a new information technology September 19th, 2016

Quantum Computing

NREL discovery creates future opportunity in quantum computing: Research into perovskites looks beyond material's usage for efficient solar cells September 9th, 2016

NREL Discovery Creates Future Opportunity in Quantum Computing: Research into perovskites looks beyond materialís usage for efficient solar cells September 1st, 2016

Colors from darkness: Researchers develop alternative approach to quantum computing August 31st, 2016

Diamonds and quantum information processing on the nano scale August 31st, 2016

Discoveries

Fighting cancer with sticky nanoparticles September 27th, 2016

Gold nanoparticles conjugated quercetin inhibits epithelial-mesenchymal transition, angiogenesis and invasiveness via EGFR/VEGFR-2 mediated pathway in breast cancer September 27th, 2016

UNAM develops successful nano edible coating which increases life food September 27th, 2016

Crystalline Fault Lines Provide Pathway for Solar Cell Current: New tomographic AFM imaging technique reveals that microstructural defects, generally thought to be detrimental, actually improve conductivity in cadmium telluride solar cells September 26th, 2016

Announcements

Oxford Instruments systems now facilitate water purification technology September 27th, 2016

Dr Barbara Armbruster promoted to Worldwide Sales and Marketing Director for XEI Scientific September 27th, 2016

Fighting cancer with sticky nanoparticles September 27th, 2016

Gold nanoparticles conjugated quercetin inhibits epithelial-mesenchymal transition, angiogenesis and invasiveness via EGFR/VEGFR-2 mediated pathway in breast cancer September 27th, 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