What’s going on with the reports of a room-temperature superconductor?

What about those other superconductors?

The news comes at a somewhat awkward time for the field. A similar claim was made about a high-pressure material a few years ago, but that paper ended up being retracted because of problems with some of its data. The same research group came back with a different material that was said to work at room temperature, but that work hasn't been replicated, and the head of the lab has now been accused of scientific misconduct.

There is almost no overlap between that work and LK-99. None of the people involved are the same, so there's no reason to suspect problematic research practices. And the chemistry and physics involved are completely different. The earlier work used high pressure to create chemicals with lots of hydrogen and unusual orbital structures. LK-99 uses no hydrogen at all and gets its orbital structures via a conformational change in a crystal lattice that takes place at ambient pressures.

Hydrogen was the focus of the earlier work because its low atomic weight influences the behavior of vibrations within the material in a way that promotes the formation of superconducting pairs of electrons. The mechanism behind LK-99 is less clear, but clearly not that.

(The LK-99's creators suggest that the conformational change in the crystal creates a sort of standing wave of electrons called a "charge density wave," and superconductivity involves electrons tunneling between wave sites. The modeling paper, by contrast, suggests that giving electrons the opportunity to both superconduct and participate in additional processes like charge density wave formation increases the probability that they'll superconduct. In any case, neither idea involves phonons.)

So when will we actually know anything?

Hopefully soon. The researchers behind the original report are trying to get information out there. In addition to the drafts placed in the arXiv, they have already published a paper on LK-99, albeit in their native Korean. And a group of South Korean scientists working in the field have also announced that they're going to obtain LK-99 samples and try to confirm its reported behavior.

There's also lots of activity outside of South Korea. Producing LK-99 is within reach of a lot of labs, and testing it is much easier since it doesn't require low temperatures or high pressures. That will mean a lot of short-term confusion, but it's likely to enable a consensus to emerge sooner.

Whether or not this chemical superconducts at ambient temperatures might not be the final question, though. Assuming it does, there will be many questions about how to develop it into a useful material, how much current it can carry, and how to use it most effectively in the huge range of applications it can be put to. But I'm sure we'll all be happy if we end up needing answers to those questions.