Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > A new look below the surface of nanomaterials

Abstract:
Scientists can now look deeper into new materials to study their structure and behavior, thanks to work by an international group of researchers led by UC Davis and the Lawrence Berkeley National Laboratory and published Aug. 14 by the journal Nature Materials.

A new look below the surface of nanomaterials

Davis, CA | Posted on August 16th, 2011

The technique will enable more detailed study of new types of materials for use in electronics, energy production, chemistry and other applications.

The technique, called angle-resolved photoemission, has been used since the 1970s to study materials, especially properties such as semiconductivity, superconductivity and magnetism. But the technique allows probing to a depth of only about a nanometer beneath the surface of a material, a limit imposed by the strong inelastic scattering of the emitted electrons.

The breakthrough work of the UC Davis/LBNL team made use of the high-intensity X-ray source operated by the Japanese National Institute for Materials Sciences at the SPring8 synchrotron radiation facility in Hyogo, Japan, and allowed researchers to look far deeper into a material, providing more information and reducing surface effects.

"We can now take this to much higher energies than previously thought," said Chuck Fadley, professor of physics at UC Davis and the Lawrence Berkeley Lab, who is senior author of the paper.

The technique is based on the photoelectric effect described by Einstein in 1905: When a photon is shot into a material, it knocks out an electron. By measuring the angle, energy and perhaps the spin of the ejected electrons, scientists can learn in detail about electron motion and bonding in the material.

Previously, the technique used energies of about 10 to 150 electron-volts. Working at the Japanese facility, Fadley and his colleagues were able to boost that to as high as 6,000 electron-volts — energies that increased the probing depth up to 20-fold.

Thanks to recent advances in electron optics, the team was also able to collect accurate information using specially designed spectrometers — effectively cameras for electrons.

The spectrometer is rather like a pinhole camera, Fadley noted. It's easy to get a sharp image with a pinhole camera by keeping the entrance opening small. Open up this aperture and a lot more light is admitted, but a clear image becomes more difficult to extract. But new developments in electron optics, particularly in Sweden, have made it possible to detect sufficient electrons to carry out such experiments.

Several high-powered X-ray sources are now running or being built in Europe and Asia, although none are yet planned in the U.S., Fadley said. The new technique could be used both for basic and commercial research on new materials for electronics and technology.

Fadley noted that he had first proposed the idea of using a high-intensity X-ray source to look more deeply beneath the surface of materials around 1980, but neither the X-ray sources nor the spectrometers existed to make the experiment feasible.

Important theoretical contributions to the work were made by Warren Picket, professor and chair of physics at UC Davis, and his research team, and Hubert Ebert of Ludwig Maximillian University, and his research team in Munich. Picket and Ebert are both co-authors of the paper.

Other co-authors are Alexander Gray, Christian Papp, and Benjamin Balke at UC Davis and the Lawrence Berkeley National Laboratory, with Papp now at the University of Erlangen and Balke now at the University of Mainz; Erik Ylvisaker at UC Davis; Shigenori Ueda, Yoshiyuki Yamashita, and Keisuke Kobayashi at the National Institute for Material Science, Hyogo, Japan; Lukasz Plucinski and Claus Schneider at the Peter Gruenberg Institute, Juelich, Germany; and Jan Minár and Juergen Braun at Ludwig Maximillian University, Munich, Germany.

The work was funded by the Nanotechnology Network Project of the Japanese Ministry of Education, Culture, Sports, Science and Technology, with additional financial support from the Deutsche Forschungsgemeinschaft and the Bundesministerium für Bildung und Forschung in Germany.

####

For more information, please click here

Contacts:
Charles Fadley
Physics
(530)752-8788


Andy Fell
UC Davis News Service
(530) 752-4533

Copyright © UC Davis

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

International research team discovers new mechanism behind malaria progression: Findings provide a new avenue for research in malaria treatment April 27th, 2015

More is less in novel electronic material: Adding electrons actually shrinks the system April 27th, 2015

Graphenea celebrates fifth anniversary April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Chemistry

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

Cacao Seed Extract Used in Production of Catalytic Nanoparticles April 27th, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

New class of 3D-printed aerogels improve energy storage April 22nd, 2015

Expanding the reach of metallic glass April 22nd, 2015

Superconductivity

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

Chip Technology

Two-dimensional semiconductor comes clean April 27th, 2015

Surface matters: Huge reduction of heat conduction observed in flat silicon channels April 23rd, 2015

Drexel materials scientists putting a new spin on computing memory April 22nd, 2015

Printing Silicon on Paper, with Lasers April 21st, 2015

Announcements

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

The 16th Trends in Nanotechnology International Conference (TNT 2015) unveils 25 Keynote Speakers: Call for abstracts open April 27th, 2015

Graphenea celebrates fifth anniversary April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Energy

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

'Holey' graphene for energy storage: Charged holes in graphene increase energy storage capacity April 22nd, 2015

Expanding the reach of metallic glass April 22nd, 2015

Research partnerships

International research team discovers new mechanism behind malaria progression: Findings provide a new avenue for research in malaria treatment April 27th, 2015

More is less in novel electronic material: Adding electrons actually shrinks the system April 27th, 2015

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

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