Too Good to Be True? Researchers Claim the World’s First Room-Temperature Superconductor
For the past couple of weeks, the internet has been abuzz with the news that a team of South Korean researchers may have successfully created the world’s first superconductor that works at room temperature and at ambient pressure.
The development has kicked off a race between experts and DIY enthusiasts alike to replicate the results, though some in the scientific community remain cautiously skeptical about whether this actually represents a breakthrough. If true, such a material could be potentially revolutionary, opening the way to things like facilitating the manufacture of levitating maglev trains and quantum computers.
Study co-authors Sukbae Lee and Ji-Hoon Kim from the Quantum Energy Research Centre, and Young-Wan Kwon from the KU-KIST Graduate School of Converging Science and Technology, first published their work on July 22 on arXiv, the open-access repository of scientific pre-prints that are not yet peer-reviewed.
Today might have seen the biggest physics discovery of my lifetime. I don’t think people fully grasp the implications of an ambient temperature / pressure superconductor. Here’s how it could totally change our lives.
— Alex Kaplan (@alexkaplan0) July 26, 2023
In their paper, the team outlines how they synthesized the superconducting material that they are calling LK-99. The process to create LK-99 involves readily available tools like a mortar and pestle, as well as a combination of lead, oxygen, sulfur and phosphorus to create lead apatite. In this case, the team combined a lead sulfate with a copper-phosphorus compound, which was then heated to 925°C in a vacuum chamber.
This process allows the copper to alter the orientation of different atoms and bonds within the molecular structure. This sample was then tested to see how much a small sample of it could resist electricity at different temperatures. The team found that the modified lead apatite’s electrical resistance decreased dramatically as the temperature was lowered, with resistivity going down to nearly zero at room temperature.
Notably, LK-99 appears to exhibit one of the peculiar attributes common to all superconductors. As demonstrated in the team’s video, LK-99 partially floats when placed on a magnet. This property, known as the Meissner effect, occurs when a magnetic field is pushed out of a material when it becomes superconducting, giving the impression that it is levitating. In the researchers’ video, it appears that the sliver of LK-99 is being repelled off the surface of the magnet — albeit not completely, which the team has attributed to possible impurities in the sample.
Holy Grail or Hype?
The team’s work is potentially significant, as most materials have some level of electrical resistance. Resistance is like a kind of friction, but for electrical energy; this resistance results in electrical energy being lost as heat, which makes such materials less efficient as an electrical conductor. For instance, metals generally have low resistivity, while wood has a high electrical resistance.
A superconductor, on the other hand, is a material that can carry an electrical current without any resistance occurring, though depending on the type of material it is made up of, it may require cooling the material down to absolute zero, or putting it under intense pressure forces for superconductivity to happen.
Previous scientific work in the last several decades has shown that when certain elemental metals like lead, mercury, niobium and tin are combined into alloys, they can be transformed into superconductors when they are cooled to absolute zero. Since then, more recent but controversial work has attempted to create a room-temperature superconducting material, though these findings still remain to be independently verified.
The chatter I’m hearing on the room temperature superconductor discovery has gone from mostly negative to cautiously optimistic over the last 24-48 hours. If this is really real, it’s huge. Amazing for the planet.
— Eric Berger (@SciGuySpace) August 2, 2023
Currently, most superconducting materials function only at extremely low temperatures or high pressure. For instance, a magnetic resonance imaging (MRI) machine is essentially an electromagnet that is made with superconducting wire, which allows it to create a strong electromagnetic field without consuming large amounts of electricity or losing it in the form of heat. But most current MRI machines require the wires to be continually bathed in liquid helium in order to keep them at low temperatures, making the machines very bulky.
Thus, for many experts in the fields of physics and materials science, a superconductor that works at both ambient temperature and pressure is the holy grail — an almost miraculous material that would pave the way for portable MRI machines, and other possibilities like hyper-efficient electrical grids, improved particle accelerators, ultra-fast digital circuits, and more stable quantum computers.
Experts Remain Skeptical in Race to Replicate Results
Since the announcement of the team’s report, there has been a flurry of activity as scientists at other reputable institutions have been attempting to either prove or disprove the results by replicating them.
Among them is Varda Space Industries engineer Andrew McCalip, who has been working diligently to reproduce LK-99 in the lab for the last several days. It appears that he may have succeeded: on August 4, McCalip posted a video that shows a tiny fragment that floats and twists above a magnet, with the addendum: “Have to take a breather for 24 hours. We made the rocks, got to a super interesting result, an epic video, now I’ve got to catch up on the rest of life for a day. Let’s take the weekend to regroup, catch up on the flood of papers, and figure out how this will be studied over the next few months. Right now I don’t think it’s enough material to be studied, but let’s talk through it. What a week.”
Meissner effect or bust: Day 8.5
We made the rocks pic.twitter.com/ygVOATBaHD
— Andrew McCalip (@andrewmccalip) August 4, 2023
Besides McCalip, other experts at Argonne National Laboratory and Huazhong University of Science and Technology (HUST) are purportedly in the process of reproducing specimens similar to the initial study, with the latter reporting success in their attempt to synthesize LK-99 and to replicate the characteristics typically associated with superconductivity.
So far, other citizen scientists have also been posting their experiments on platforms like TikTok, Twitch, and Twitter, as well as Chinese social media sites such as Bilibili. The most salient of these efforts are being documented in a user-friendly online list that is being updated daily, with another one here with more technical details.
Despite all the hype, most scientists remain skeptical about whether this is really a breakthrough moment in history. Some, like Argonne National Laboratory’s Michael Norman, cautioned on Science that it will take time to verify the team’s work, which appears to have been hastily published among dramatic in-fighting behind the scenes.
“They come off as real amateurs,” said Norman. “They don’t know much about superconductivity, and the way they’ve presented some of the data is fishy.”
Another potential blow to the team’s credibility came late last week when the Korea Joongang Daily reported that the team’s supposed affiliations with local companies and research institutes may have been made up.
Moreover, a committee set up by the Korean Society of Superconductivity and Cryogenics (KSSC) recently invalidated the results, telling the news outlet that “data from the studies published by Quantum Energy Research Centre indicates different physical properties from that of a typical superconducting material… it can be argued that the movement of the specimen shown in the footage [of the superconductor released by Quantum Energy Research Centre] can be recreated with materials that are not superconductive.”
Nevertheless, these developments haven’t stopped people from forging ahead anyway to corroborate the results, and there still remains a lot of conflicting information between all these concurrent efforts. In the meantime, it’s unclear whether the hype will prove to be true, as replication of the results means just that — that the information in the team’s paper is confirmed, and not that LK-99 is actually a superconductor. The scientific process rarely follows a direct path, but requires trial and error — and lots of it — before something can be verified with absolute certainty, so it’s a matter of waiting to see what will ultimately hold up to scientific scrutiny.