THE MYSTERY OF A HIGH-TEMPERATURE SUPERCONDUCTOR
Date: Friday, August 27, 2004 @ 23:39:59 GMT
With equipment so sensitive that it can locate clusters of electrons, Cornell University and University of Tokyo physicists have -- sort of -- explained puzzling behavior in a much-studied high-temperature superconductor, perhaps leading to a better understanding of how such superconductors work.
It turns out that under certain conditions the electrons in the material pretty much ignore the atoms to which they are supposed to be attached, arranging themselves into a neat pattern that looks like a crystal lattice. The behavior occurs in a phase physicists have called a "pseudogap," but because the newly discovered arrangement looks like a checkerboard in scanning tunneling microscope (STM) images, J.C. Seamus Davis, Cornell professor of physics, calls the phenomenon a "checkerboard phase." ...
The discovery only leads to more questions. Theoretically, Davis says, this arrangement should not conduct electricity at all, because the electrons are locked into their crystal-like pattern. "It's always been a mystery, how do you get from an insulator through a tiny change to a superconductor," he notes. "Having empirical knowledge of what this phase is may help us to get from here to there." ...
Source: Cornell University
Article from: http://www.physorg.com/news962.html