Mini-Throughput: Floaty Rock Edition

Photo by Hyun-Tak Kim, CC BY 4.0 <https://creativecommons.org/licenses/by/4.0>, via Wikimedia Commons

So, the one question I have been asked for the last week, over and over, is what I thought of the Oppenheimer movie. I am preparing a video review that I will post here. But the second question is about the reported room-temperature superconductor. Is it real? Is it fake? Will it make my iPhone better?

Well, let’s back up.

Every material in existence, as far as we know, resists the passage of electrons through it. But that resistance varies. For some materials, which we call conductors, the resistance is low. So we use these to pipe electricity all over the world. Other materials, which we can insulators, have high resistance and we use them to keep electricity confined to where it should be. But even the best conductors have some resistance. So when electricity flows through them, some energy is lost as waste heat.

About a century ago, however, it was discovered that, under certain conditions, some materials become superconductive. The resistance abruptly drops to zero. These materials also eject magnetic fields, which means that magnets will float over them. For a long time, this only happened at extremely low temperatures. But in the 1980s, the theoretically impossible happened — superconductivity was found in materials above the temperature of liquid nitrogen. This not only expanded the practical applications of superconductors — MRI machines use them — it raised the tantalizing possibility of room-temperature superconductors, materials that did not require any special conditions to superconduct. Over the last few years, such materials have been found, but only at extreme pressure. And some of those claims are in dispute or have been disproven.

It’s hard to overstate how revolutionary it would be if we developed a room-temperature superconductor. It would mean huge increase in grid efficiency, basically a giant wad of free carbon-neutral energy. It would mean massive gains in computing power, cheap maglev trains and even better electronics.

So you can understand the excitement when, a couple of weeks ago, two papers appeared on the online preprint server arXiv claiming to have produced a room-temperature and ambient pressure superconductor. The material could apparently be created quite easily in a lab in a short period of time. But then confusion erupted as people wondered what the hell was being claimed. The papers had obvious errors and flaws which the authors claimed was a result of a team member going rogue and putting the paper out before it was ready. Labs around the world are trying to replicate the process but it’s not clear what exactly what was done and we have conflicting claims on the initial results. You can read a somewhat tongue-in-cheek summary here. A more serious summary concludes:

Two independent research teams, one in India and the other in China, claimed to have recreated LK-99 and confirmed the structure aligned with the original paper, but neither found evidence of superconductivity. A levitating sample of LK-99 has been reported at another lab in China, but that doesn’t necessarily prove superconductivity either. Research into the properties of LK-99 by Sinead Griffin at the Lawrence Berkeley National Laboratory found that superconductivity was one explanation for the results, but that “a wealth of other phenomena like metal insulator transitions, charge density waves” and others could explain the results. The material seems to at least be unusual, and researchers are continuing to dig into its properties.

The obvious parallel is cold fusion. Commercially-viable nuclear fusion has been a goal of plasma physics for decades. In 1989, a group claimed to have achieved it with a tabletop apparatus at room temperature. However, investigation by other groups failed to reproduce the results. The parallels are somewhat disturbing: the cold fusion team were also somewhat opaque about their technique, also lacked expertise in some of the relevant fields and were also pursuing a somewhat fringe theory of how a challenging physical process could be achieved.

It’s impossible to draw any strong conclusions under these circumstance. We are still in the early days of more reputable labs trying to both figure out what was done and reproduce it in laboratory conditions. So at this point, the long and short of it is this:

• The development of a room-temperature and ambient-pressure superconductor would be the biggest technological breakthrough since Ben Franklin got a buzz from a kite.
• The circumstances of this discovery are very sus. I suspect that what they have found is a different physical effect that, while interesting, is not superconductivity. Included in this possibility is that while they haven’t discovered room temperature superconductivity, they have found something that will lead to it.
• However, we are in the early phases of replication. In a few weeks, we should know one way or the other.

So my response to this is a shrug emoji. It could be the most important discovery in our lifetimes. It could be nothing. It could be anywhere in between. But the good news is that science works. And it’s working now. And so watch this space when the final results are in.