Fall into the (pseudo)gap

Despite their name, “high-temperature” superconductors require pretty darn cold conditions — all far below freezing temperatures, some near absolute zero (-273 degrees Celsius) — to operate without energy loss. As a result, they’re not practical for everyday uses like more efficient power transmission — that is, unless you have a stockpile of liquid helium or nitrogen dewars just hanging around your house.

So why can’t we create room-temperature superconductors? That’s a question that scientists are still trying to answer.

In research released today in the journal Nature, a team of U.S. and Japanese researchers has made a breakthrough in understanding an alleged killer of room-temperature superconductivity — an electronic phase called the “pseudogap.”

Using copper-oxide superconductors, the group found a fundamental difference in how electrons behave at the two distinct oxygen sites within the material while in the pseudogap phase. This could be a significant step in figuring out exactly what the pseudogap is and how it affects superconductivity.

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.

You can read more here.