What Happened With LK-99?
Physics has long sought to find a material that could serve practically as a room-temperature superconductor to carry electricity with zero resistance. A physics pre-print was posted on July 31st, and updated August 3rd, to arxive.org claiming that a material, LK-99, was a room-temperature superconducting material.
It became an internet and social media sensation overnight. And rightfully so. Labs were able to replicate parts of the experiment adding to the evidence that this was a breakthrough. Such a discovery would have a huge impact on many fields.
However, scientists were skeptical after trying to replicate other parts of the experiment. By August 16th, enough scientists had attempted replication to determine that LK-99 was, in fact, not a room-temperature superconductor.
So what happened? Dan Garisto, writing for Nature, compiled the evidence and explains how this happened:
Researchers seem to have solved the puzzle of LK-99. Scientific detective work has unearthed evidence that the material is not a superconductor, and clarified its actual properties.
The conclusion dashes hopes that LK-99 — a compound of copper, lead, phosphorus and oxygen — marked the discovery of the first superconductor that works at room temperature and ambient pressure. Instead, studies have shown that impurities in the material — in particular, copper sulfide — were responsible for the sharp drops in electrical resistivity and partial levitation over a magnet, which looked similar to properties exhibited by superconductors.
Essentially, impure samples created properties that resulted in ferromagnetism. This ferromagnetism mimicked some of the expected properties of a room-temperature superconductor. The ferromagnetism was the key to concluding that the initial result was not valid.