50 years ago, superconductors were warming up

Excerpt from the March 16, 1974 issue of Science News

A photograph of a diamond anvil used to crush materials at high pressures and ultracold temperatures.

To create superconductors, physicists use diamond anvils (one shown) to crush materials at high pressures and ultracold temperatures. Researchers are searching for materials that can superconduct at ambient pressure and room temperature.

J. Adam Fenster/University of Rochester

Superconductors inch upwardScience News, March 16, 1974

Superconductivity, the property by which certain metals lose all their electrical resistance, would be a grand thing to use technologically were it not for the extreme refrigeration necessary. Every superconductor has a transition temperature above which it becomes an ordinary conductor. Most transition temperatures are near absolute zero. [Scientists] are discovering metals with higher transition temperatures.

Update

Transition temperatures continue to creep upward. In 2018, physicists reported that a compound of lanthanum and hydrogen under extreme pressure showed signs of superconductivity up to about −20° Celsius — the highest for any superconductor (SN: 10/13/18, p. 6). But the squeeze and relative chill makes these materials impractical for widespread use, so the hunt for a material that superconducts at room temperature and closer to atmospheric pressure continues. A debunked 2023 claim for such a material has some scientists advocating for new standards for identifying superconductivity (SN: 12/16/23 & 12/30/23, p. 22).

Lillian Steenblik Hwang is the associate digital editor at Science News Explores. She has a B.S. in biology from Georgia State University and an M.S. in science journalism from Boston University.