Lower the temperature of any conductive material, and you’ll see its resistance decrease proportionally. If the material in question happens to have superconductive properties however, there will be a certain critical temperature below which resistance drops to *zero*, meaning that an electric current through a loop of superconductive wire can persist forever, without power source.

That is of course provided that the temperature doesn’t rise above the critical threshold for the given material. Unfortunately that threshold usually hovers around 4.2 Kelvin. To put that number in context, think of Pluto, the astral body furthest out in our solar system, where temperatures may go as low as 33 degrees Kelvin. In wintertime.

It’s a real pity that superconductivity requires such very low temperatures to work, because it means real world use-cases are pretty much limited to medical devices like MRI’s, most popular flavors of quantum computers (not all though), and the Japanese CSMaglev train. (That’s not counting some pretty exotic weaponry).

Useful as those applications are, the potential is so much bigger than that. If we could figure out how to achieve superconductivity at higher temperatures, it could be the enabling technology for large scale electrification of air traffic, not to mention the key to making fusion based energy production work at scale (I’ve written previously about some exciting developments in this space).

So where do we currently stand?

Well the theory behind superconductivity was discovered in 1911, and has since resulted in no less than five Nobel prizes. The first in 1913, followed by subsequent ones in 1972, 1973, 1987 and most recently in 2003. This suggests the field isn’t trivial, there aren’t just kinks to be worked out, but also lots of basic science to get right.

It also suggests, however, that we’re making real progress. And indeed there seem to be cause for some optimism, however cautious. So called High Temperature Superconductors—HDS—can theoretically be operated at between 65 and 93 K, which is veritably toasty compared to 4.2, but still not altogether practical, especially not since costs remain astronomical.

The commonly used cost metric for superconductors is dollars per kiloampere-meter, or $/kA-m. Prices currently range from $150 to $200/kA-m and analysts seem to agree that 50 will mean a tipping point (this paper predict a future cost as low as 10).

What’s driving this drop in price, is an increasing demand for superconductors thanks to the recent surge in interest in fusion based energy production, where many of the experimental reactors around the world rely on HDS technology. In addition to that, CERN is also looking at replacing their current Large Hadron Collider with a future version which will be cooled by High Temperature Superconductors. All of which has led to a 10-fold increase in HDS production capacity in the last three years alone.

If you’re not excited yet, things might be about to get seriously, spectacularly, dramatic. Or perhaps not, the jury is still out. Here’s what recently happened:

Three years ago, Ranga Dias of University of Rochester got a paper published in Nature, claiming his group had achieved superconductivity at *room temperature*.

That was about as big a deal as deals get in science.

Only then Nature retracted the paper, claiming that the results it reported couldn’t be replicated. When something like that happens, the scientists are usually shamed into silence. Not this time however, all nine authors vehemently claim that they stand by their results.

But the story isn’t over there. Earlier this year, the same team made a comeback in Nature, again claiming evidence of “near-ambient superconductivity“. Within hours, Science published a story about it where the first word of the heading—revolutionary—is put between apostrophes. Nature itself is a little milder but still hedges its bets, saying that Hopes raised for room-temperature superconductivity, but doubts remain.

If Dias and his team has indeed made what would amount to the biggest scientific breakthrough of the 21st century, then why don’t they do what they can to counter the skeptics?

That question was emphatically answered as recently as in April, when this patent application, filed in July 2022, became public. Then one week ago exactly, Dias went on record—again in an interview with Science—saying he did indeed plan on commercializing his findings, within his newly founded startup Unearthly Materials.

If the claims hold, I reckon we’ll see a lot more about that company in the near future. I for one am keeping my fingers crossed!