European team announces superconductivity breakthrough

a reply to: TEOTWAWKIAIFF
Finally...

I thought they´d announce it late 2018 that´s why I wrote wait until 2019 in that other thread about EV/superconductivity

Until they develop a working and reliable motor/generator windings from that copper oxide, I won´t hold my breath. I know a company that did that already and went public in early 2018 with it.

Over the past few years I have seen post on threads (usually blogs) about room temperature superconductors (RTS). One site in particular keeps on posting anything and everything that the blogger runs across as "major announcement" news. Last year it was graphite by some group in Japan; last month, it RTS in graphene doped with whatever and he was complaining science has not acknowledged this "breakthrough discovery" or something.

Around the same the same a paper hit the arXiv also claiming a RTS. Even our intrepid blogger who gloms onto any RTS news stayed away. In fact, nearly everybody looked at the news, the source, and the material, and shook their head in one big, "Puhleez."

Now, finally, somebody has put up an article about that arXiv paper.

TheWire.in, Aug. 6, 2018 - Did IISc Team Find a Room-Temperature Superconductor? The Devil's in the Details.

The ".in" should tell you something. It is a very detailed piece about a team, also in India, who claimed they observed RTS in a combinations of nano-silver and nano-gold, at ambient temperature. Me, that was all I had to see before the Red Flag went off.

The article details the history of superconductivity and HTS research (my previous post covers the same). Then they turn a critical eye towards the gold/silver RTS paper. First, they did not do a temperature graph. Second the diamagnetic property that SC show (you know, the magnet floating above the other magnet as liquid nitrogen is poured over it? That), was never demonstrated and dismissed as "sintering process error" (manufacturing of the RTS). Next, the fact that gold and silver belong to "monovalent metal" where the electrons do not form Cooper pairs no matter how much they are cooled. Another point being, they studied this at cold temperature!! Then claimed some form of magic happens as you make it thinner and refined by some chemical process, idk, that it would work at room temperature.

Last but not least is what immediately set off my BS O'meter and the Red Flags. These guys are from India. If you ever known Indians then you know there absolute adoration of gold. Well, some of them REALLY love and the others like it a lot. I've had a co-worker trying to show off some 14K ring he just purchased and from what I remember, it was already turning green! So to me, this desire to get a revered precious metal to be "magical" and a RTS made me feel sad for the authors.

Otherwise, a good collection of dates and temperatures for various HTS and steps towards the dream of RTS! Also a good reminder of all the things that go into SC (the triumvirate also mentioned in previous post). Last, a great example, IMO, of confirmation bias.

Rice physicists Pengcheng Dai and Andriy Nevidomskyy and their colleagues used simulations and neutron scattering experiments that show the atomic structure of materials to reveal tiny distortions of the crystal lattice in a so-called iron pnictide compound of sodium, iron, nickel and arsenic.

These local distortions were observed among the otherwise symmetrical atomic order in the material at ultracold temperatures near the point of optimal superconductivity. They indicate researchers may have some wiggle room as they work to increase the temperature at which iron pnictides become superconductors.

phys.org, Aug. 7, 2018 - Physicists find surprising distortions in high-temperature superconductors.

This is not really a HTS people are really interested in but it is "odd" and this team decided to take a look at it in detail.

To make any material superconductive, it must be cooled. That sends it through three transitions: First, a structural phase transition that changes the lattice; second, a magnetic transition that appears to turn paramagnetic materials to antiferromagnets in which the atoms' spins align in alternate directions; and third, the transition to superconductivity. Sometimes the first and second phases are nearly simultaneous, depending on the material.

There is our triumvirate again. Temperature, magnetism, lattice transition. The article is about the 2 years the team spent looking at the lattice structure. There is a bunch of technical jargon about square and brick shaped lattice deformation as temperature drops within the HTS. The "simultaneously" aspect has frustrated researchers as they cannot "see" what happens first which then informs theory (remember HTS is not a settled theory, yet).

The article goes on to explain that at a fairly high temperature a deformation of the lattice appears. The iron in the sample lines up like cubes then parts of it get tugged out of shape ("orothombic" in the article, just think, "trapezoid a bit and no longer cubes"). This is typical when superconductivity appear after the magnetic phase collapses. But they were seeing pockets of it happen earlier than the magnetic phase which precedes the SC phase!

The thinking is this, if iron does this in this material, then there might be room to kick the effect in in other materials where iron is a component. They called it "wiggle room" (same source) in driving up the HTS Tc. And who knows, maybe get the same effect in other materials or at least vary the recipe a bit and drive Tc up even further.

HMMMM

Now just soak that copper dioxide in red wine.