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Pressure-induced high-temperature superconductivity retained at ambient (arxiv.org)
86 points by agarttha 32 days ago | hide | past | favorite | 29 comments

The submitted title is incorrect. The actual article title is "Pressure-induced high-temperature superconductivity retained at ambient". The abstract doesn't make the claim of superconductivity at room temperature at 1 ATM.

Fixed now. Submitted title was "Room temperature superconductivity at 1 ATM for 7 days".

Submitters: please don't rewrite titles like that. It's against the site guidelines:

"Please use the original title, unless it is misleading or linkbait; don't editorialize."


My apologies for the title change due to a misreading. Won’t happen again.



> We have also observed that some phases remain stable without pressure at up to 300 K and for at least 7 days.

not imply the 7days are at ambient pressure?

>suggesting that this PQed non-SC phase is stable up to 300 K

See page 5. The phase is stable but does not superconduct at that temperature.

It seems that by "ambient" they mean ambient pressure but not ambient temperature.

I'm a layperson skimming in a hurry, but it looks like this is actually "our findings with material A may be transferable to material B", which is very close to a room-temp superconductor but doesn't seem to be the same thing as "here, I have a chunk of it on my desk".

to quote the conclusion:

"In conclusion, we have demonstrated that the pressure-induced/enhanced superconducting phases with high Tc and the pressure-induced semiconducting phases in FeSe and Cu-doped FeSe can be stabilized at ambient without pressure by pressure-quenching at chosen pressures and temperatures. Theses pressure-quenched phases have been shown to be stable at up to 300 K and for up to at least 7 days. The observations suggest that the recently reported room-temperature superconductivity in hydrides close to 300 GPa may be retained without pressure, making possible the ubiquitous applications of superconductivity envisioned"

Note this is about phase metastability, and not RT, 1ATM high Tc. They don't claim that in the actual article, just that phases like high Tc phases survive at 1ATM. There is __no way in hell__ that they would have published this, if they hadn't already tried the viable RTS phases, and they didn't work. It would have been literally giving away a Nobel prize to any other group which could race to do it first.

In that case, I would think that they'd note that they weren't able to get it to work for materials with much high Tc.

You must have never submitted a paper for peer review :P The incentive is to make the paper seem as important as possible, the hope it could work is impact, they would never admit such experiments.

The patents alone would have been worth a fortune beyond imagination.

Imagine this being a turning point in human history. This seemingly mundane HN post links to humanities defining discovery for centuries. This begins a path that takes us to the stars and a post scarcity species.

More likey there's some deal breaking issue. The pop-sci sites wave it from the rooftops for a few weeks then we forget about it.

Edit: fixed first sentence

I am not a physicist, let alone the right kind of physicist, but from the abstract it looks like the transition temperature is 35K. That is a long long way away from "room temperature".

> We have also observed that some phases remain stable without pressure at up to 300 K and for at least 7 days.

300K = 80F

It doesn't superconduct at 300 K, the metastable phase can survive heating to 300 K and superconducting will resume when cooled back down to 26 K.

"Some phases" (a few molecules?) appeared to have to be stable at 300K for a week. Whatever. I've been writing and reading about cold fusion hype since the 1980s, still waiting for my maglev vacuum cleaner.

Phases typically imply a thermodynamically large quantity. It makes no sense to describe the phase of a handful of particles.

Keep reading: “We have also observed that some phases remain stable without pressure at up to 300 K and for at least 7 days.

Iron selenide in those phases does not superconduct at room temperature. The authors have a "strong belief" that other room temperature high pressure superconductors will retain superconductivity at atmospheric pressure using their technique even though the one they studied doesn't.

The usual Fairbanks room temperature superconductors.

It seems like they're describing a phenomenon where a material remains in a metastable configuration associated with a higher critical temperature, even after the pressure is removed and the sample warmed to room temperature.

That said, the Tc of this phase is still fairly low at about 30+ K, so this does not superconduct at room temperature, regardless of the pressure.

The title is incorrect. Can we have a correction?

>retaining, at ambient via pressure-quenching (PQ), its Tc up to 37 K

>suggesting that this PQed non-SC phase is stable up to 300 K

non-SC means "not superconducting"

This isn't quite RTS, but it's a breakthrough step towards it. If this pressure-quenching concept can be applied to some of the more exotic high-temperature superconductors (~300K) that usually require hundreds of GPa, it might result in superconductivity at room-temperature and pressure.

So, totally uninformed here -- why exactly is superconductivity a big deal? What would it change for us?

Imagine electrical energy being transferred with zero loss to heat. That's superconductivity.

Strong magnets for nuclear fusion reactor.

Other applications: https://en.wikipedia.org/wiki/Technological_applications_of_...

Transmission of power with reduced/no loss, maglevs become a reality, computers can become much faster with much less/no loss of power to heat.

Anything that conducts electricity or operates with a magnetic field becomes hyper efficient, imagine how many modern machinery depends on those principles.

Big if true

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