Is LK-99 Really a Room-Temperature Superconductor?

TL;DR

Independent attempts had not confirmed that LK-99 superconducts at room temperature and ambient pressure, so the claim remained unproven. Simulations suggested unusual electronic properties but supplied no decisive evidence. The episode also examines subseafloor carbon storage, NASA’s loss of contact with Voyager 2, Euclid’s first images, and a blood test intended to indicate Alzheimer’s risk before symptoms appear.

Transcript

hello welcome back to New Scientist weekly your curated selection of the week science stories I'm Timothy Revel in New York and I'm Christy Taylor in a slightly different location in New York welcome to the show this week we learn about a test that could let you know if you're at risk of developing Alzheimer's before... Read More

Key Insights

• LK-99 remained an unconfirmed room-temperature superconductor because independent experiments had not reproduced superconductivity at room temperature and ambient pressure. Two research groups reported no superconductivity, while another reported a possible transition only at about -163 degrees Celsius.
• The original LK-99 evidence came from two preprints that had not undergone peer review. Those drafts described a production method and measurements interpreted as signs of superconductivity, prompting researchers to scrutinize both the experimental methods and the material itself.
• Sample preparation is a central uncertainty in testing LK-99. The material appears difficult to create, and one original researcher attributed failed replications to insufficient sample purity, although the available results did not establish that impurity was the actual cause.
• Computer simulations found unusual electron properties when they assumed that LK-99’s atoms were arranged exactly as its creators reported. Those properties allowed superconductivity to remain plausible, but the calculations could neither simulate it directly nor prove that the material must superconduct.
• Convincing evidence for LK-99 would require multiple characteristic measurements rather than one suggestive result. The physics reporter remained skeptical and emphasized the need for additional experiments, thorough data, and independent confirmation of the full set of behaviors expected from a superconductor.
• A room-temperature, ambient-pressure superconductor could transform technologies that rely on electrical conduction. The episode identifies MRI systems and more compact, commercially viable nuclear fusion among possible applications, while stressing that the scientific stakes make careful verification essential.
• Subseafloor carbon storage could lock carbon dioxide into basalt through reactions that form solid calcium carbonate. The proposed Solid Carbon project targets young basalt in the Cascadia Basin, about 200 kilometers, or 120 miles, west of Vancouver Island.
• Induced seismicity is a recognized concern for geological carbon storage because injecting large quantities of carbon dioxide could cause smaller faults to slip. Such movement might create hazards or allow stored gas to escape, although the proposed site is far from the major Cascadia fault.

Questions & Answers

Q: Is LK-99 a room-temperature superconductor?

The evidence discussed does not confirm that LK-99 is a room-temperature, ambient-pressure superconductor. Two independent teams, one in India and one in China, reproduced the material using the published steps but found no superconductivity. A separate Chinese group reported a measurement suggesting possible superconductivity near -163 degrees Celsius, far below room temperature. More experiments and more complete measurements were still needed.

Q: Why did scientists remain skeptical of the LK-99 claims?

Scientists remained skeptical because the original claims appeared in two preprints that had not yet been peer reviewed, and independent teams had not reproduced the central room-temperature result. Simulations identified unusual electronic properties but did not directly demonstrate superconductivity. The physics reporter also stressed that a convincing superconductor must display several characteristic behaviors, so one suggestive measurement would not be sufficient evidence.

Q: What did independent LK-99 replication attempts find?

Two independent research groups, based in India and China, made LK-99 according to the procedures described by its creators and performed preliminary superconductivity tests. Neither group found superconductivity. Another independent Chinese team reported a measurement indicating that the material might superconduct at about -163 degrees Celsius, or -261 degrees Fahrenheit, but that result did not validate superconductivity at room temperature or ambient pressure.

Q: Can computer simulations prove that LK-99 superconducts?

The simulations described in the episode cannot prove that LK-99 superconducts. They assumed that its atoms were arranged exactly as the original researchers reported, then used quantum theory and substantial computing resources to examine electron behavior. Several calculations found unusual electron properties compatible with the possibility of superconductivity, but the method could not simulate superconductivity directly or show that those properties necessarily produce it.

Q: Why is making a reliable LK-99 sample difficult?

The chemistry and preparation of LK-99 appear to be important parts of the uncertainty. The original researchers provided steps for creating it, but independent samples may differ in purity or atomic arrangement. One original researcher blamed failed replications on samples that were not pure enough and said he was communicating with other researchers, although it remained unclear whether impurity actually explained their negative results.

Q: Why would room-temperature superconductivity matter?

A material that perfectly conducts electricity at room temperature and ambient pressure could have broad scientific and technological applications. The episode mentions MRI systems and the possibility of helping make nuclear fusion more compact and commercially viable. It would also represent a major breakthrough in condensed-matter physics after a search lasting roughly 50 to 60 years, which helps explain both the excitement and the demand for rigorous verification.

Q: How would carbon dioxide storage in subseafloor basalt work?

The proposed approach would inject millions of tons of carbon dioxide into young basalt beneath the seafloor in the Cascadia Basin, about 200 kilometers, or 120 miles, west of Vancouver Island. Over time, the carbon dioxide would react with basalt and form solid calcium carbonate. Researchers estimated that the basin’s basalt could store about 750 billion tons, with conversion taking less than 135 years.

Q: Could the Cascadia carbon storage project cause earthquakes?

Injecting large quantities of carbon dioxide underground can produce induced seismicity, in which pressure causes smaller faults to slip. Such movement could create a hazard or allow stored carbon dioxide to leak, undermining the purpose of storage. However, the proposed injection location is described as far from the major Cascadia fault associated with the region’s large earthquake risk, so that specific fault is not connected to the project.

Summary & Key Takeaways

• LK-99 attracted intense scrutiny after its creators released two unreviewed preprints describing how to make it and reporting measurements consistent with superconductivity at room temperature and ambient pressure. Researchers, along with citizen scientists working in garages and kitchens, rapidly attempted to reproduce the material and test its electrical behavior.

• Two independent groups in India and China reported no superconductivity in their preliminary tests. Another Chinese team reported a measurement suggesting superconductivity near -163 degrees Celsius, or -261 degrees Fahrenheit, rather than at room temperature. The original researchers argued that unsuccessful replications may have used samples that were not sufficiently pure.

• The episode also discusses proposed carbon dioxide storage in basalt beneath the Cascadia Basin, NASA’s loss of contact with Voyager 2, Euclid’s first images, and an Alzheimer’s risk blood test. Additional topics include energy-storing house foundations, an ocean-floor Maillard reaction, and the oldest known jellyfish fossil.