It has been over a hundred years since researchers discovered that some materials can conduct electricity perfectly. Such a superconductor could be transformative for science and technology, but all claims of creating one that would work at room temperature and pressure, including recent studies of a material named LK-99, have proven controversial.

Superconductivity was discovered in 1911 when physicist Heike Kamerlingh Onnes noticed that a mercury wire cooled to about -269°C (-452°F) doesn’t resist the flow of electricity. Within a few years materials …