Featured Research

from universities, journals, and other organizations

A new look below the surface of nanomaterials

Date:
August 17, 2011
Source:
University of California - Davis
Summary:
Scientists can now look deeper into new materials to study their structure and behavior. A new technique will enable more detailed study of new types of materials for use in electronics, energy production, chemistry and other applications.

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.

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 Minαr 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 fόr Bildung und Forschung in Germany.


Story Source:

The above story is based on materials provided by University of California - Davis. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. X. Gray, C. Papp, S. Ueda, B. Balke, Y. Yamashita, L. Plucinski, J. Minαr, J. Braun, E. R. Ylvisaker, C. M. Schneider, W. E. Pickett, H. Ebert, K. Kobayashi, C. S. Fadley. Probing bulk electronic structure with hard X-ray angle-resolved photoemission. Nature Materials, 2011; DOI: 10.1038/nmat3089

Cite This Page:

University of California - Davis. "A new look below the surface of nanomaterials." ScienceDaily. ScienceDaily, 17 August 2011. <www.sciencedaily.com/releases/2011/08/110816152248.htm>.
University of California - Davis. (2011, August 17). A new look below the surface of nanomaterials. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2011/08/110816152248.htm
University of California - Davis. "A new look below the surface of nanomaterials." ScienceDaily. www.sciencedaily.com/releases/2011/08/110816152248.htm (accessed April 17, 2014).

Share This



More Matter & Energy News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Small Reactors Could Be Future of Nuclear Energy

Small Reactors Could Be Future of Nuclear Energy

AP (Apr. 17, 2014) — After the Fukushima nuclear disaster, the industry fell under intense scrutiny. Now, small underground nuclear power plants are being considered as the possible future of the nuclear energy. (April 17) Video provided by AP
Powered by NewsLook.com
Honda's New ASIMO Robot, More Human-Like Than Ever

Honda's New ASIMO Robot, More Human-Like Than Ever

AFP (Apr. 17, 2014) — It walks and runs, even up and down stairs. It can open a bottle and serve a drink, and politely tries to shake hands with a stranger. Meet the latest ASIMO, Honda's humanoid robot. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
German Researchers Crack Samsung's Fingerprint Scanner

German Researchers Crack Samsung's Fingerprint Scanner

Newsy (Apr. 16, 2014) — German researchers have used a fake fingerprint made from glue to bypass the fingerprint security system on Samsung's new Galaxy S5 smartphone. Video provided by Newsy
Powered by NewsLook.com
Porsche CEO Says Supercar Is Not Dead: Cue the Spyder 918

Porsche CEO Says Supercar Is Not Dead: Cue the Spyder 918

TheStreet (Apr. 16, 2014) — The Porsche Spyder 918 proves that, in an automotive world obsessed with fuel efficiency, the supercar is not dead. Porsche North America CEO Detlev von Platen attributes the brand's consistent sales growth -- 21% in 2013 -- with an investment in new technology and expanded performance dynamics. The hybrid Spyder 918 has 887 horsepower and 944 lb-ft of torque, but it can run 18 miles on just an electric charge. The $845,000 vehicle is not a consumer-targeted vehicle but a brand statement. Video provided by TheStreet
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