Experts stay grounded over levitating ‘breakthrough’

South Koreans have claimed one of the holy grails of science: superconductors that can be used at room temperature.

In a clip released by Korean scientists their nugget of lead, copper and phosphate is seen to partially float above a magnet

This much scientists can agree on: there was some levitation. This they can also agree on: the levitation appeared to involve no prior refrigeration.

What they can’t yet agree on is: does this mean we have a panacea for our problems, a room-temperature superconductor?

Or, as teams around the world scramble to replicate the results, is this merely the latest in a long line of claimed wonder materials that turn out to be nothing of the sort?

Last week, South Korean scientists uploaded a video showing a nugget of lead, copper and phosphate partially floating above a magnet. They also published a paper that explained the findings.

It was titled The First Room-Temperature Ambient Pressure Superconductor. But what does that mean? In plain English, the physicist Sabine Hossenfelder said: “It means, basically, ‘Please give us a Nobel prize’.”

A superconductor is a mat­erial that allows electric current to pass without resistance. In doing so, it also expels all magnetic fields, causing it to float above magnets.

Superconductors are not a fantasy – they exist in every MRI machine – but, at present, for them to work they must be very cold. This limits their use.

If, however, you could use them at room temperature, the possibilities are mind-boggling. You could run electricity grids with minimal power loss; build compact and powerful magnets for fusion plants; make better levitating trains.

It would, says Susie Speller, of Oxford University’s department of materials, “be transformational”. Or, as the paper from Korea University in Seoul puts it, perhaps getting a little ahead of the peer review process: “We believe that our new development will be a brand-new historical event that opens a new era for humankind.”

Professor Speller is not celebrating yet. Like many in a field not used to being the subject of intense public speculation, she has watched the online reaction to the findings with bemusement.

“The experts tend to come across as quite lukewarm compared to the general public,” she said. “It makes us seem a bit bad-tempered.”

The problem is, they’ve been here before. They even have a term for it. “We call them USOs,” said Michael Norman, from the Argonne National Laboratory in the US. “Unidentified Superconducting Objects.”

The data uploaded by the ­Koreans, he said, did not provide all the necessary information, such as convincingly showing a drop to zero resistance.

It also didn’t prove the levitation was caused by what is known as the Meissner effect. This is key. At materials science conferences – where they have all the best parties – Dr Norman recalls how delegates once entertained themselves with a supercooled floating skateboard.

A warmer version could yet be on the way. In Dr Norman’s laboratory, they have followed the instructions in the South Korean paper, and are synthesising the material. Other laboratories doing the same. Around the world, people are preparing to test its conductance, test its resistance, see whether it floats.

If it is a superconductor then a lot of work still needs to be done. Identifying the material is just the start. You have to work out how to make it into wires, how to use it in circuits.

“If it really is true, then obviously we’re going to drop a lot of what we’re doing and focus almost solely on this,” Professor Norman said.

So when does he expect us to have an answer? “It wouldn’t surprise me if we know in a week.”

The Times