Energy News  
Study Gives Lowdown On High-Temperature Superconductivity

coils of wire and other sundry products in row 12 is the dream of super conductive material science
by Staff Writers
Toronto - Mar 04, 2004
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.

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 V�lker, 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."

Community
Email This Article
Comment On This Article

Related Links
University of Toronto
SpaceDaily
Search SpaceDaily
Subscribe To SpaceDaily Express
Powering The World in the 21st Century at Energy-Daily.com



Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News


Europe Debates Nuclear Energy
Washington (UPI) Jan 11, 2006
European Union countries are starting to rethink their opposition to nuclear energy amid a dispute between Russia and Ukraine over natural gas supplies, but energy analysts say a switch still lacks a green light.







  • Mitsubishi Electric Seals Solar Panel Contract With
  • Study Gives Lowdown On High-Temperature Superconductivity
  • Fuel Cell Reaches Milestone
  • Compact Fuel Cells Could Oust Batteries

  • Yucca Mountain Site Must Make Use Of Geological Safety Net
  • New Jersey Physicist Uncovers New Information About Plutonium
  • Complex Plant Design Goes Virtual To Save Time And Money
  • Volcanic Hazard At Yucca Mountain Greater Than Previously Thought





  • NASA Uses Remotely Piloted Airplane To Monitor Grapes



  • Hewitt Pledges Support For Aerospace Industry
  • National Consortium Picks Aviation Technology Test Site
  • Wright Flyer Takes To The Sky In Las Vegas
  • Aurora Builds Low-speed Wind Tunnel

  • Los Alamos Hopes To Lead New Era Of Nuclear Space Tranportion With Jovian Mission
  • Boeing Selects Leader for Nuclear Space Systems Program
  • Boeing-Led Team to Study Nuclear-Powered Space Systems
  • Boeing To Build Space-borne Power Generator

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement