Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


Home > Press > Spintronic Materials Show Their First Move

Physicists trace the "hopping" of single electrons in magnetic materials

Spintronic Materials Show Their First Move

Los Angeles, CA | March 22, 2005

How much energy does it take for an electron to hop from atom to atom, and how do the magnetic properties of the material influence the rate or ease of hopping? Answers to those questions could help explain why some materials, like those used in a computer hard drive, become conductors only in a magnetic field while they are very strong insulators otherwise. They might also help scientists learn how to use the electron's "spin" (a property analogous to the spinning of a child's toy top), as well as its charge, to carry information in a new field known as spintronics. Stéphane Grenier, a postdoctoral fellow studying electronic excitations, or "electron hopping," at the U.S. Department of Energy's Brookhaven National Laboratory, will describe the techniques he uses and the properties of these materials at the March 2005 meeting of the American Physical Society in Los Angeles, California. His talk will take place on Monday, March 21, at 2:30 p.m. in room 151 of the Los Angeles Convention Center.

"We are looking at something very local, electrons hopping between a pair of atoms, to help us understand important macroscopic effects," Grenier says. "This information could help predict which materials might have the properties needed for particular applications -- say, increasing the storage capacity of computer hard drives -- and direct the fabrication of new materials in which these properties are optimized."

To determine the energy needed by an electron to hop from one atom to another atom, Grenier used a technique called inelastic x-ray scattering at the Advanced Photon Source at Argonne National Laboratory. He shines x-ray light onto the sample and measures the tiny difference in energy between the incoming and outgoing photons. This difference is the amount of energy needed to move the electrons.

He used this technique to study materials with different magnetic "lattices" -- ferromagnetic and antiferromagnetic. In ferromagnetic materials, the atoms' magnetic moments (that is, their spins) are all aligned in the same direction. In antiferromagnetic materials, the magnetic moments of the adjacent atoms point in opposite directions.

"When the magnetic moments are aligned, the electron hopping is increased between particular atoms. That is, more electrons make the jump to their neighbors, and it takes less energy to move them," Grenier says. "While this has been known for a while, we have shown the direction in which the electrons move and exactly what price they 'pay,' in terms of energy, to move, and the influence the magnetic lattice of the material has on this hopping."

The electrons want to align their own magnetic moments, or spins, with that of the atoms in the lattice, he explains. "They will do so only if all the atoms' magnetic moments are aligned -- that is when the 'fare' for hopping has its lowest price," he said.

Electrons moving with their spins aligned in the same direction make a current of spins, which could be used, somewhat like currents of electrical charge are now used, to pass or transform information in future electronic components made of tailored magnetic lattices -- a future generation of circuits based on the science of "spintronics," which is also carried out at Brookhaven Lab.

Grenier's studies, along with theoretical analysis of the materials, may also help scientists understand why some materials possess properties such as superconductivity and "colossal magnetoresistance," the ability of some strong insulators to become good conductors when induced by a magnetic field.

Studies on atomic magnetism have applications for understanding novel materials -- including spintronic materials and superconductors -- that will revolutionize the electronic and energy industries. Such studies using x-rays can only be performed in the U.S. at x-ray synchrotron radiation facilities built and managed by the U.S. Department of Energy's Office of Science.

This research was funded by the Office of Basic Energy Sciences within the U.S. Department of Energy's Office of Science.


One of the ten national laboratories overseen and funded primarily 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 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:

Karen McNulty Walsh
631 344-8350

Mona S. Rowe
631 344-5056

Copyright © BNL

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.

Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Possible Futures

Discovery about new battery overturns decades of false assumptions October 7th, 2015

Superconductivity trained to promote magnetization: Russian scientist and her colleagues discovered the superconductivity effect, which will help to create future supercomputers October 6th, 2015

Nanoscale photodetector shows promise to improve the capacity of photonic circuits: Researchers at the University of Rochester have fabricated a device in which light can induce a current using a silver nanowire -- an important step toward harnessing light to speed up the next ge October 6th, 2015

Big range of behaviors for tiny graphene pores: Like biological channels, graphene pores are selective for certain types of ions October 6th, 2015


Superconductivity trained to promote magnetization: Russian scientist and her colleagues discovered the superconductivity effect, which will help to create future supercomputers October 6th, 2015

Physicists find new explanation for key experiment: Researchers at Bielefeld University publish findings on spin caloritronics and are the first to apply measurement methods in the field September 24th, 2015

First realization of an electric circuit with a magnetic insulator using spin waves September 14th, 2015

Spintronics: Molecules stabilizing magnetism: Organic molecules fixing the magnetic orientation of a cobalt surface/ building block for a compact and low-cost storage technology/ publication in Nature Materials July 25th, 2015


8th Int'l Iran Nano 2015 Festival Kicks Off Work October 7th, 2015

Latest Hygienic Products Presented in Iran Nano 2015 October 7th, 2015

From trees to power: McMaster engineers build better energy storage device October 7th, 2015

Discovery about new battery overturns decades of false assumptions October 7th, 2015

The latest news from around the world, FREE

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

Nanotechnology Now Featured Books


The Hunger Project

Car Brands
Buy website traffic