Featured Research

from universities, journals, and other organizations

Study Gives Lowdown On High-temperature Superconductivity

Date:
March 5, 2004
Source:
University Of Toronto
Summary:
A new study by theoretical physicists at the University of Toronto and the University of California at Los Angeles (ULCA) could bring scientists one step closer to the dream of a superconductor that functions at room temperature, rather than the frigid temperatures more commonly found in deep space.

Microscopic image of a ceramic superconductor.
Credit: Michael W. Davidson, Florida State University

A new study by theoretical physicists at the University of Toronto and the University of California at Los Angeles (ULCA) could bring scientists one step closer to the dream of a superconductor that functions at room temperature, rather than the frigid temperatures more commonly found in deep space.

Related Articles


The findings, which appear in the March 4 issue of the journal Nature, identify three factors that explain a perplexing pattern in the temperatures at which multi-layered ceramic materials become superconductors. The study could advance research in medical imaging, electrical power transmission and magnetically levitating trains. Its authors are U of T physics professor Hae-Young Kee and post-doctoral fellow Klaus Vφlker, and Professor Sudip Chakravarty of UCLA's physics and astronomy department.

Superconductivity is a phenomenon that occurs when certain metals are cooled to near absolute zero, a temperature equivalent to zero degrees Kelvin (K), -273 C or -459 F. In ceramic materials, the phenomenon appears at about 100K. At a so-called critical temperature--that varies depending on the number of layers within the ceramic substance--the material becomes capable of conducting electricity without any energy loss.

Despite the value of such an efficient system, the supercooling--usually done with liquid nitrogen or liquid helium--makes superconductors impractical for many applications. "A room temperature superconductor would be a revolution, but even a superconductor with a higher critical temperature would have extremely important implications for multiple industries," says Kee, who holds the Canada Research Chair in Theoretical Condensed Matter Physics.

Materials scientists have developed a group of "high-temperature" superconductors made with layers of copper oxides sandwiched between insulating filler material. This material reaches critical temperatures in the range of roughly 130K--the highest know critical temperatures to date. Previous studies on superconductors have established that while the critical temperature rises as the number of layers increase from one to three, it then drops off. By the time the number of layers rises to seven, the critical temperature has fallen below that of the single-layer superconductor.

Scientists have previously suggested that the critical temperature increase between one- and three-layered materials is due to the ability of electron pairs to tunnel between the layers of superconducting material.

Now, Kee and her colleagues have identified the factors that combine with a mechanism--known as the competing order--that lowers a superconductor's critical temperature in materials with more than three layers. That "competing order," in turn, is dependent on an uneven distribution of electrons, resulting in a charge imbalance between the material's multiple layers. Kee and her colleagues are the first group to put these three factors--the tunnelling, the competing order and the charge imbalance--together.

"If we can find a way to affect the charge imbalance, we could suppress the competing order and develop superconducting materials with higher and higher critical temperatures," says Kee. "And if you can push the superconducting temperature higher, then it will become much cheaper to apply this technology."

The research was funded by the U.S. National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, the Canadian Institute of Advanced Research, the Canada Research Chairs program and the Alfred P. Sloan Foundation.


Story Source:

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


Cite This Page:

University Of Toronto. "Study Gives Lowdown On High-temperature Superconductivity." ScienceDaily. ScienceDaily, 5 March 2004. <www.sciencedaily.com/releases/2004/03/040304072747.htm>.
University Of Toronto. (2004, March 5). Study Gives Lowdown On High-temperature Superconductivity. ScienceDaily. Retrieved April 21, 2015 from www.sciencedaily.com/releases/2004/03/040304072747.htm
University Of Toronto. "Study Gives Lowdown On High-temperature Superconductivity." ScienceDaily. www.sciencedaily.com/releases/2004/03/040304072747.htm (accessed April 21, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Tuesday, April 21, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Maine Storm Surge Sparks Power Explosions

Raw: Maine Storm Surge Sparks Power Explosions

AP (Apr. 21, 2015) — Police dash cam video shows a series of explosions along the beach in Maine as heavy storm surge soaked electrical transformers. (April 21) Video provided by AP
Powered by NewsLook.com
Japan's Maglev Train Breaks New World Speed Record

Japan's Maglev Train Breaks New World Speed Record

AFP (Apr. 21, 2015) — Japan&apos;s state-of-the-art maglev train clocks a new world speed record in a test run near Mount Fuji, smashing through the 600 kilometre (373 miles) per hour mark, as Tokyo races to sell the technology abroad. Video provided by AFP
Powered by NewsLook.com
Free Home Heating Offered by E-Radiators

Free Home Heating Offered by E-Radiators

Reuters - Innovations Video Online (Apr. 21, 2015) — A revolutionary new radiator design offers Dutch home-owners the chance to get free heating. The e-Radiator is a computer server modified so that the heat it generates can warm a room inside a house. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Humanoid Robot Can Recognise and Interact With People

Humanoid Robot Can Recognise and Interact With People

Reuters - Innovations Video Online (Apr. 20, 2015) — An ultra-realistic humanoid robot called &apos;Han&apos; recognises and interprets people&apos;s facial expressions and can even hold simple conversations. Developers Hanson Robotics hope androids like Han could have uses in hospitality and health care industries where face-to-face communication is vital. Matthew Stock 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