Science / Medicine : Promising Conductivity Work

<i> From Times staff and wire service reports </i>

The creation of three new superconducting ceramics suggests that a whole new class of materials could overcome some of the problems associated with finding the perfect electrical conductor, a UC San Diego physicist said last week. Unlike more conventional superconducting metals that transmit current through so-called “electron holes,” the new ceramics use extra electrons to carry electrical current, said M. Brian Maple.

The new materials could be a precursor to superconductors--materials that carry electricity with no losses due to resistance--that operate at higher temperatures and do not need costly coolants, said Maple. His team is the first in the United States to make the new ceramics. The new materials could “overcome some of the problems associated with previously known superconductors, such as low amounts of electrical current. Materials discovered within this category may be able to carry more current than existing materials,” he added.

The new materials involve combinations of copper oxide with rare earth elements such as praseodymium, neodymium or europium and small amounts of either cerium or thorium.