Featured Research

from universities, journals, and other organizations

Nano-sonar Uses Electrons To Measure Under The Surface

Date:
March 2, 2009
Source:
Helmholtz Association of German Research Centres
Summary:
Just as sonar sends out sound waves to explore the hidden depths of the ocean, electrons can be used by scanning tunneling microscopes to investigate the well-hidden properties of the atomic lattice of metals. Scientists have now succeeded in making bulk Fermi surfaces visible in this manner. Fermi surfaces determine the most important properties of metals.

The Fermi surface around a cobalt atom embedded in copper. The colours represent the curvature of the surface, which determines the reflection properties for electron waves.
Credit: Forschungszentrum Jülich

Just as sonar sends out sound waves to explore the hidden depths of the ocean, electrons can be used by scanning tunnelling microscopes to investigate the well-hidden properties of the atomic lattice of metals.

Related Articles


As researchers from Göttingen, Halle and Jülich now report in the journal Science, they succeeded in making bulk Fermi surfaces visible in this manner. Fermi surfaces determine the most important properties of metals.

"Fermi surfaces give metals their personality, so to speak," explained Prof. Stefan Blügel, Director at the Jülich Institute of Solid State Research. Important properties, such as conductivity, heat capacity and magnetism, are determined by them. On the Fermi surfaces inside the atomic union, high-energy electrons are in motion. Depending on what form the surfaces have and what mobility is assigned to the electrons, they determine the physical properties of metals.

In their latest publication, the researchers report on how they used a scanning tunnelling microscope to direct electrons into a copper sample. As electrons spread out like waves, they pass through the metal and are scattered and reflected at obstacles in the bulk, such as single cobalt atoms. "The overlap between incoming and outgoing waves is so strong," said Dr. Samir Lounis from Forschungszentrum Jülich who turned the theoretical calculations into an experiment, "that they can be measured as spherical patterns on the surface using the scanning tunnelling microscope."

The somewhat deformed rings on the surface allow us to draw direct conclusions on the shape of the Fermi surfaces and the depth of the cobalt atoms, similar to how sonar recognises the ocean floor by means of reflected sound waves. "We hope that more sophisticated methods will make it possible to gain a detailed understanding of deep impurities and interfaces between atomic lattices," explained Lounis. For his simulations of the scanning tunnelling experiment, he used the supercomputer known as JUMP in the Jülich Supercomputing Centre.

In a related article in the "Perspectives" section of "Science", the innovative approach is praised. A scanning tunnelling microscope is primarily used to characterise the surface of a sample. Thanks to the theoretical work in Jülich, it can now be used to gain a direct insight into the bulk of solids and to understand interesting effects in the nanoworld.


Story Source:

The above story is based on materials provided by Helmholtz Association of German Research Centres. Note: Materials may be edited for content and length.


Journal Reference:

  1. Weismann et al. Seeing the Fermi Surface in Real Space by Nanoscale Electron Focusing. Science, 2009; 323 (5918): 1190 DOI: 10.1126/science.1168738

Cite This Page:

Helmholtz Association of German Research Centres. "Nano-sonar Uses Electrons To Measure Under The Surface." ScienceDaily. ScienceDaily, 2 March 2009. <www.sciencedaily.com/releases/2009/02/090227130931.htm>.
Helmholtz Association of German Research Centres. (2009, March 2). Nano-sonar Uses Electrons To Measure Under The Surface. ScienceDaily. Retrieved March 2, 2015 from www.sciencedaily.com/releases/2009/02/090227130931.htm
Helmholtz Association of German Research Centres. "Nano-sonar Uses Electrons To Measure Under The Surface." ScienceDaily. www.sciencedaily.com/releases/2009/02/090227130931.htm (accessed March 2, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Monday, March 2, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

HTC And Valve Team Up For Virtual Reality Headset

HTC And Valve Team Up For Virtual Reality Headset

Newsy (Mar. 1, 2015) — HTC unveiled Vive, its new virtual reality headset, Sunday. The device is supported by gaming company Valve, which has made a push into the market. Video provided by Newsy
Powered by NewsLook.com
Rehab Robot Helps Restore Damaged Muscles and Nerves

Rehab Robot Helps Restore Damaged Muscles and Nerves

Reuters - Innovations Video Online (Mar. 1, 2015) — A rehabilitation robot prototype to help restore deteriorated nerves and muscles using electromyography and computer games. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Elon Musk's Hyperloop Moves Forward

Elon Musk's Hyperloop Moves Forward

Buzz60 (Feb. 27, 2015) — Zipping around at 800-miles an hour is coming closer to reality in California. An entire town is being built around Elon Musk&apos;s Hyperloop concept and it wants you to stop in for a ride when it&apos;s ready. Brett Larson is on board. Video provided by Buzz60
Powered by NewsLook.com
Vibrating Bicycle Senses Traffic

Vibrating Bicycle Senses Traffic

Reuters - Innovations Video Online (Feb. 26, 2015) — Dutch scientists have developed a smart bicycle that uses sensors, wireless technology and video to warn riders of traffic dangers. Ben Gruber reports. Video provided by Reuters
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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