Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

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

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Aculon Hires New Business Development Director December 19th, 2014

Iranian Scientists Use Nanotechnology to Increase Power, Energy of Supercapacitors December 18th, 2014

Chemistry

How does enzymatic pretreatment affect the nanostructure and reaction space of lignocellulosic biomass? December 18th, 2014

The gold standard December 9th, 2014

Simple, Biocompatible Method Developed for Production of Cerium Oxide Nanoparticles December 9th, 2014

Nanocatalysts Can Reduce Pollution Caused by Diesel Engines December 4th, 2014

Green meets nano: Scientists at TU Darmstadt create multifunctional nanotubes using nontoxic materials December 3rd, 2014

Superconductivity

Nanoscale resistors for quantum devices: The electrical characteristics of new thin-film chromium oxide resistors that can be tuned by controlling the oxygen content detailed in the 'Journal of Applied Physics' December 9th, 2014

Unusual Electronic State Found in New Class of Unconventional Superconductors: Finding gives scientists a new group of materials to explore to unlock secrets of some materials' ability to carry current with no energy loss December 8th, 2014

Chip Technology

Instant-start computers possible with new breakthrough December 19th, 2014

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

Pb islands in a sea of graphene magnetise the material of the future December 16th, 2014

Stanford team combines logic, memory to build a 'high-rise' chip: Today circuit cards are laid out like single-story towns; Futuristic architecture builds layers of logic and memory into skyscraper chips that would be smaller, faster, cheaper -- and taller December 15th, 2014

Announcements

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Aculon Hires New Business Development Director December 19th, 2014

Energy

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

How does enzymatic pretreatment affect the nanostructure and reaction space of lignocellulosic biomass? December 18th, 2014

Iranian Scientists Use Nanotechnology to Increase Power, Energy of Supercapacitors December 18th, 2014

Lifeboat Foundation gives 2014 Guardian Award to Elon Musk December 16th, 2014

Research partnerships

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Unraveling the light of fireflies December 17th, 2014

Scientists trace nanoparticles from plants to caterpillars: Rice University study examines how nanoparticles behave in food chain December 16th, 2014

FEI and Oregon Health & Science University Install a Complete Correlative Microscopy Workflow in Newly Built Collaborative Science Facility December 16th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE