We started out being skeptical, but cautiously optimistic. Then, the bad news just kept rolling in.
Claims of a room temperature and ambient pressure superconductor have torn the scientific community apart. But as more evidence gathers, the existence of a miraculous lead-based metal that can perfectly conduct electricity at room temperature is seriously starting to fall apart.
The latest nail in the coffin is a failed replication test conducted by researchers at Charles University in the Czech Republic.
“The possibilities within the claims of Lee, Kim et al. would be a game-changer for society if they would turn out to be true, so we of course wanted to be part of the history in case of a real breakthrough,” materials scientist Ross Colman, who participated in the test, told Physics World.
But as far as Colman’s team could tell, the test didn’t end up with a superconductor. The material, dubbed LK-99 in a pair of of un-peer-reviewed papers by South Korean researchers, simply refuses to reliably behave like one.
That’s despite controversial claims of Chinese researchers calculating that LK-99’s electronic structures could hint at hallmark qualities of superconductors. Videos circulating online also purported to show a small sample of the material at least partially levitating, which is one, but not the only, telltale sign of a superconductor.
The excitement led to countless home lab replication attempts, with varying degrees of success, triggering a frenzy on social media.
Yet far more evidence points towards the material being a plain old conventional semiconductor.
“A lot of the stuff early on was rushed and statements from all sides were unchecked,” Andrei Bernevig, a condensed-matter theorist at Princeton University, told Physics World. “The social media, memes, etc., have been completely detrimental to progress in this field in my view… I hope we never do science like this again.”
A big reason for the mass confusion is the “messy” recipe for LK-99, according to Colman.
“Whilst the synthesis recipe is presented very simply, there are a number of inaccuracies or missing information,” he told the publication.
So what the hell is the material anyways, if it isn’t a superconductor? A lot of evidence points towards it being ferromagnetic, much like iron, and diamagnetic, which means it can readily be magnetized within a magnetic field.
Another wrinkle in the story could be impurities present in the samples the original South Korean researchers used that may have resulted in greatly skewed results.
“If there’s a simple alternative explanation for the results, there’s no reason to consider the extraordinary claim of room-temperature superconductivity anymore,” Michael Fuhrer, a condensed-matter physicist at Monash University, Australia, told Physics World.
“The experimental papers showing ferromagnetism were pretty convincing, and the new theories are also more carefully done,” Richard Greene, a superconductor researcher at the University of Maryland, told Scientific American.
“It is still a bit too early to put the nail in the coffin,” he added. “But we are getting close. The coffin is there, the nails are ready, and a hammer is ready, too.”
More on superconductors: That Room-Temperature Superconductor Seems to Be Falling Apart