Number 227 (Story #2), May 22, 1995 by Phillip F. Schewe and Ben Stein A CURRENT DENSITY OF A MILLION AMPS PER SQ CM has been achieved in a YBaCuO superconductor at a temperature of 77 K. Representing a team of Los Alamos scientists, Stephen Folytyn reported at last month's Materials Research Society meeting that their material even remains superconducting while carrying currents of 500,000 A/cm**2 in a magnetic field of 8 Tesla. The Los Alamos sample consisted of thin layers of YBCO deposited on a flexible metal tape. For applications in magnet windings, superconductors must not only carry high currents in the presence of strong fields, but must also be ductile enough to be worked into flexible wires. Scientists at Los Alamos and other labs are striving to find the right process (the fewer production steps the better) that will result in spools of wire kilometers long. (Science News, 29 Apr.; Science, 5 May; Nature, 11 May.)