High-temperature Superconductivity

Most recent answer: 10/22/2007

Q:
There is a type of ceremic which can become a superconductor at about -197 degree celsius. What property does this material possess to make it able to become a superconductor at such a relatively high temperature (other materials are superconductors at a much lower temp.)
- Anonymous
A:
You’ve asked a great question. People have been trying to figure out why a number of oxide compounds superconduct at rather high temperatures for over 15 years now. There’s been some progress, but not any one answer that everybody agrees on.
One of the main theories of some high-temperature superconductors is based on a coupling between electrons due to their mutual coupling to short-range magnetic fluctuations. The magnetic fluctuations play the same role that sound waves play in ordinary superconductors.
I think that all the high-temperature superconductors have sheets of fairly good conductor partially isolated by poorly conducting sheets. This nearly two-dimensional property of the conducting sheets seems to be important in letting them form superconducting order without freezing into some sort of other order (e.g. magnetism) that tends to arise in normal 3-D materials.

Mike W.

(published on 10/22/2007)