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Superconductors inch upward — Science 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).
