Featured Research

from universities, journals, and other organizations

Lack Of Thermoelectric Effect Is Cool Feature In Carbon Nanotubes

Date:
January 18, 2009
Source:
University of Illinois
Summary:
Metallic carbon nanotubes have been proposed as interconnects in future electronic devices packed with high-density nanoscale circuits. But can they stand up to the heat?

Jean-Pierre Leburton, left, a professor of electrical and computer engineering, and physics graduate student Marcelo Kuroda collaborated on theory that explains the absence of the thermoelectric effect in metallic carbon nanotubes.
Credit: Photo by L. Brian Stauffer

Metallic carbon nanotubes have been proposed as interconnects in future electronic devices packed with high-density nanoscale circuits. But can they stand up to the heat?

Recent experiments have shown the absence of the thermoelectric effect in metallic carbon nanotubes. Building upon earlier theoretical work, researchers at the University of Illinois say they can explain this peculiar behavior, and put it to good use.

“Our work shows that carbon nanotubes that come in metallic form have different thermal and electrical properties than normal conductors,” said Jean-Pierre Leburton, the Gregory Stillman Professor of Electrical and Computer Engineering at Illinois and co-author of a paper published in the Dec. 19 issue of the journal Physical Review Letters, and in the Jan. 5 issue of the Virtual Journal of Nanoscale Science and Technology.

“Specifically, metallic carbon nanotubes don’t exhibit the thermoelectric effect, which is a fundamental property of conductors by which a current flows because of a temperature difference between two points of contact,” said Leburton, who is also affiliated with the Beckman Institute, the Micro and Nanotechnology Laboratory, and the Frederick Seitz Materials Research Laboratory. “This is a metal, which doesn’t behave like an ordinary metal.”

In a normal conductor, a current can be induced by applying a potential difference (voltage) or by creating a temperature difference between two contacts. Electrons will flow from the higher voltage to the lower, and from the higher temperature to the lower. There is a similarity between temperature imbalance and electric field.

In metallic carbon nanotubes, however, the lack of the thermoelectric effect means no current will flow because of temperature change between two contacts. The similarity between temperature imbalance and voltage disappears.

This is a fundamental property of metallic carbon nanotubes, Leburton said, peculiar to their particular structure. Semiconductor nanotubes, which possess a different chirality, behave differently.

Also, in normal conductors, electrons can acquire a range of velocities, with some traveling much faster than others. In metallic carbon nanotubes, however, all electrons travel at the same velocity, similar to the behavior of photons. Heating the nanotube does not change the electron velocity.

“This means metallic carbon nanotubes offer less resistance than other metal conductors,” Leburton said. “And, in high-density circuits, metallic carbon nanotube interconnects would reduce heat losses and require far less cooling than copper nanowires.”

With Leburton, physics graduate student Marcelo Kuroda is co-author of the paper. The current work is an extension of theoretical work Leburton, Kuroda and electrical and computer engineering professor Andreas Cangellaris first published in the Dec. 21, 2005, issue of Physical Review Letters.


Story Source:

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


Cite This Page:

University of Illinois. "Lack Of Thermoelectric Effect Is Cool Feature In Carbon Nanotubes." ScienceDaily. ScienceDaily, 18 January 2009. <www.sciencedaily.com/releases/2009/01/090115191940.htm>.
University of Illinois. (2009, January 18). Lack Of Thermoelectric Effect Is Cool Feature In Carbon Nanotubes. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2009/01/090115191940.htm
University of Illinois. "Lack Of Thermoelectric Effect Is Cool Feature In Carbon Nanotubes." ScienceDaily. www.sciencedaily.com/releases/2009/01/090115191940.htm (accessed August 22, 2014).

Share This




More Matter & Energy News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Is It a Plane? No, It's a Hoverbike

Is It a Plane? No, It's a Hoverbike

Reuters - Business Video Online (Aug. 22, 2014) UK-based Malloy Aeronautics is preparing to test a manned quadcopter capable of out-manouvering a helicopter and presenting a new paradigm for aerial vehicles. A 1/3-sized scale model is already gaining popularity with drone enthusiasts around the world, with the full-sized manned model expected to take flight in the near future. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Coal Gas Boom in China Holds Climate Risks

Coal Gas Boom in China Holds Climate Risks

AP (Aug. 22, 2014) China's energy revolution could do more harm than good for the environment, despite the country's commitment to reducing pollution and curbing its carbon emissions. (Aug. 22) Video provided by AP
Powered by NewsLook.com
Former TSA X-Ray Scanners Easily Tricked To Miss Weapons

Former TSA X-Ray Scanners Easily Tricked To Miss Weapons

Newsy (Aug. 21, 2014) Researchers found the scanners could be duped simply by placing a weapon off to the side of the body or encasing it under a plastic shield. Video provided by Newsy
Powered by NewsLook.com
Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. 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:
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