SCIENCE / MEDICINE : Superconductor Advance

A new type of “high-temperature” ceramic superconductor may be much easier to fabricate into useful devices such as computers than the high-temperature superconductors discovered more than a year ago, according to researchers at Sandia National Laboratories in Albuquerque, N.M.

A Sandia team announced last week that it had produced thin films of a thallium-containing superconductor, which was discovered in January, that carry electricity without any resistance at a temperature of minus 285 degrees Fahrenheit, the highest value yet recorded for thin films.

Most important, the Sandia group found that the thin film had a current-carrying capacity at least 10 times as great as the capacity of films made from the earlier ceramic superconductors, even though the film was made up of many small crystals in contact with each other. With the earlier superconductors, researchers had found that such polycrystalline materials had too low a current-carrying capacity to be useful in most applications.

Superconducting thin films, which emit no heat, would allow transistors and integrated circuits in computers to be placed much closer together, making the devices smaller and faster.