Never mind room temperature, LK-99 slammed as 'not a superconductor at all'

Enthusiasm over the purported room temperature superconductor LK-99 is waning further as more research teams are unable to reproduce the original findings. In fact, one at a US university has concluded it is not a superconductor at all.

Researchers around the world are racing to reproduce the findings from the Quantum Energy Research Centre in Seoul, which claims a material called LK-99 has superconducting properties at room temperature with ambient atmospheric pressure.

The growing consensus appears to be that this might not be the long-sought room temperature superconductor science and industry have been hoping for. Nonetheless, stocks in companies linked to superconductor technology have dropped, according to Bloomberg, after taking off following the publication of the original report in July.

Perhaps the biggest blow came from the University of Maryland's Condensed Matter Theory Center (CMTC), which is a theoretical research facility set up to "maintain sustained excellence in theoretical condensed matter physics," the study of solids and liquids.

In a series of tweets, CMTC summed up the latest findings from various research teams working on LK-99 (or copper-doped lead-apatite, if you prefer) and concluded: "With a great deal of sadness, we now believe that the game is over. LK99 is NOT a superconductor, not even at room temperatures (or at very low temperatures). It is a very highly resistive poor quality material."

These research efforts included those of the National Taiwan University, which reported that the material produced in their lab exhibited some diamagnetic properties, but did not have the hallmarks of superconductivity and zero resistance was not observed.

Also mentioned was the National Physical Laboratory of India, which likewise reported observing diamagnetism but no superconductivity, and the International Center for Quantum Materials in China, which found a small amount of ferromagnetism (not diamagnetism) in tiny flakes of LK-99, but again no superconductivity.

In fact, several of the research teams reported insulating resistivity actually increasing with decreasing temperature, leading the CMTC team to remark that LK-99 appears to be an "anti-superconductor."

• Scientists strangely unable to follow recipe for holy grail room-temp superconductor
• MIT discovery suggests a new class of superconductors
• Microsoft quantum lab retracts published paper: Readings that cast doubt on crucial discovery went AWOL
• Unprotected quantum 'puters may hit 4ms brick wall, thanks to background radiation slashing qubit lifespans

If anyone still has any doubts, we asked CTMC director Professor Sankar Das Sarma about the evidence against LK-99, and he told us:

Meanwhile, it was reported that the Korean Society of Superconductivity and Cryogenics was awaiting samples of LK-99 from the Quantum Energy Research Centre in order to conduct tests to determine the validity of its claims. However, it told Bloomberg that there had been no additional communication since the samples were promised. ®