This pattern shows the tunneling potential of electrons on oxygen atoms "north" and "east" of each copper atom (shown embedded in the pattern) in the copper-oxide layer of a superconductor in the pseudogap phase. On oxygen atoms north of each copper, the tunneling potential is strong, as indicated by the brightness of the yellow patches forming lines in the north-south direction. On oxygen atoms east of each copper, the tunneling potential is weaker, indicated by less intense yellow lines in the east-west direction. This apparent broken symmetry may help scientists understand the pseudogap phase of copper-oxide superconductors. (Credit: Image courtesy of DOE/Brookhaven National Laboratory)
Now scientists have discovered a fundamental difference in how electrons behave at the two distinct oxygen-atom sites within each copper-oxide unit, which appears to be a specific property of the non-superconducting pseudogap phase. The research -- described in the July 15, 2010, issue of Nature -- may lead to new approaches to understanding the pseudogap phase, which has been hypothesized as a key hurdle to achieving room-temperature superconductivity.
To read the rest of the article, click here.