Featured Research

from universities, journals, and other organizations

Anti-Electrons Help Researchers Find Nano-Surface Defects In Gold

Date:
December 22, 1999
Source:
Oak Ridge National Laboratory
Summary:
Tiny defects in the surface of common material - from silicon to steel -- determine the properties of material and how it can be used. Unfortunately, many of these pores, called vacancies, are so small they cannot be accurately measured.

OAK RIDGE, Tenn., Dec. 21, 1999 -- Tiny defects in the surface of common material - from silicon to steel -- determine the properties of material and how it can be used. Unfortunately, many of these pores, called vacancies, are so small they cannot be accurately measured.

In the past, measurement of vacancies has seriously limited the development of new or improved materials, such as the next generation of optical and electronic devices. This has been especially significant when the vacancies are in devices that are only a few nanometers (one millionth of a millimeter) in size.

Today an international team of researchers at the Department of Energy's Oak Ridge National Laboratory (ORNL) is applying the use of positrons, or anti-electrons, to this task with considerable success.

In a paper published in the November 29th issue of Physical Review Letters, a team from ORNL; Lucent Technologies, Inc.; Fisk University; and Japan's Electrotechnical Laboratory document an experiment using positrons to find clusters of four atomic vacancies at the surface of gold nanoparticles embedded in a magnesia matrix. These clusters of vacancies explain changes in the optical properties when the materials are subjected to different fabrication processes.

Positrons were generated by smashing gamma rays against a tungsten target at the laboratory's Oak Ridge Electron Linear Accelerator. The gamma rays divide into negatively charged electrons and their anti-matter, positrons. The decay of unstable sodium 22 provided an alternative source of positrons. The positrons are injected into the gold nano-particles, and through advanced spectroscopy, the researchers are able to determine the size, location, and concentration of the vacancy clusters.

Nanoscale science and technology is an area of interest in the Office of Science at the Department of Energy, which supported the project. Possible future applications for this work include higher speed computer chips, manipulating properties of optical devices, less brittle ceramic material, and improved fiber composite materials.

The work was done under the leadership of physicist Dr. Jun Xu of ORNL's Chemical and Analytical Sciences Division.

Oak Ridge National Laboratory is a multiprogram research facility of the Department of Energy managed by Lockheed Martin Energy Research Corporation.


Story Source:

The above story is based on materials provided by Oak Ridge National Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

Oak Ridge National Laboratory. "Anti-Electrons Help Researchers Find Nano-Surface Defects In Gold." ScienceDaily. ScienceDaily, 22 December 1999. <www.sciencedaily.com/releases/1999/12/991222075649.htm>.
Oak Ridge National Laboratory. (1999, December 22). Anti-Electrons Help Researchers Find Nano-Surface Defects In Gold. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/1999/12/991222075649.htm
Oak Ridge National Laboratory. "Anti-Electrons Help Researchers Find Nano-Surface Defects In Gold." ScienceDaily. www.sciencedaily.com/releases/1999/12/991222075649.htm (accessed July 26, 2014).

Share This




More Matter & Energy News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. 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