Ambient Temperature/Pressure Superconductors

[Recusant]

There was a claim made a few months ago that wasn't really borne out (one paper already retracted, a second likely to be retracted). Now another comes along, from a completely different team. Not peer reviewed yet, so don't hold your breath. However, it would be a significant development, potentially changing our technology in amazing ways.

"A room-temperature, ambient-pressure superconductor? Take a closer look" | The Register

Three scientists in South Korea claim they've crafted a superconductor that works at both room temperature and ambient pressure – a revolutionary breakthrough if confirmed.

Superconductors – which are able to conduct electricity with virtually no resistance, and therefore have almost zero energy loss – typically require intense cold and pressure to function. In a pre-print paper, the scientific trio state they were able to produce a modified form of lead-apatite dubbed LK-99 that is superconductive at any temperature below 127°C (261°F) without the need for pressure chambers.

Such a superconductor could be useful, provided all of its physical characteristics are sound. For example, it could be used to make faster digital electronics, resulting in higher performance from personal computers. It could be used in MRI machines without the extreme cooling required, which has caused a shortage of helium. Something like LK-99 could replace the powerful magnets in maglev trains and fusion reactors. And obviously could produce super-efficient power transmission lines.

[. . .]

"All evidence and explanation lead that LK-99 is the first room-temperature and ambient-pressure superconductor," the trio claimed in their paper.

"We believe that our new development will be a brand-new historical event that opens a new era for humankind." Not to overstate things.

As far as we're aware, their study has not yet been accepted or published in a peer-reviewed journal. We've asked them for further comment.

[. . .]

The Register reached out to several physics departments and labs to get their take on the LK-99 paper, and we'll let you know what they make of it all. Professors Susannah Speller and Chris Grovenor of the University of Oxford's Department of Materials in England earlier told the i newspaper they have some doubts about the South Korean team's claims.

"It is too early to say that we have been presented with compelling evidence for superconductivity in these samples," the duo said. They added the paper was interesting, though the results weren't wholly convincing.

Two critical data points needed to ascertain the superconductivity of LK-99 – its magnetization changing as well as heat capacity – aren't evident in the data the trio presented, Profs Speller and Grovenor argued.

Another physicist, Sven Friedemann of the University of Bristol in England, shared that assessment, saying vital evidence was missing from the South Korea paper. Friedemann also questioned whether footage in the study claiming to show Meissner effect levitation due to expulsion of magnetic fields could be also caused by a non-superconducting source.

So hold the excitement, for now at least.

[Continues . . .]

The paper is available as a pre-print.

"The First Room-Temperature Ambient-Pressure Superconductor" | arXiv

For the first time in the world, we succeeded in synthesizing the room-temperature superconductor (T_c≥400 K, 127∘C) working at ambient pressure with a modified lead-apatite (LK-99) structure. The superconductivity of LK-99 is proved with the Critical temperature (T_c), Zero-resistivity, Critical current (I_c), Critical magnetic field (H_c), and the Meissner effect.

The superconductivity of LK-99 originates from minute structural distortion by a slight volume shrinkage (0.48 %), not by external factors such as temperature and pressure. The shrinkage is caused by Cu²+ substitution of Pb²+(2) ions in the insulating network of Pb(2)-phosphate and it generates the stress.

It concurrently transfers to Pb(1) of the cylindrical column resulting in distortion of the cylindrical column interface, which creates superconducting quantum wells (SQWs) in the interface. The heat capacity results indicated that the new model is suitable for explaining the superconductivity of LK-99. The unique structure of LK-99 that allows the minute distorted structure to be maintained in the interfaces is the most important factor that LK-99 maintains and exhibits superconductivity at room temperatures and ambient pressure.

[Icarus]

I read about this a few months back. I expected a great deal of media attention to the claimed breakthrough. No such excitement was forthcoming. Now a new set of claims.

Let us hope that the Korean guys have developed something as spectacular as room temperature superconductors. Skepticism abounds for now.

[Tank]

Fingers crossed this is it. Can you imagine rechargeable batteries that can be recharged in seconds?