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A room-temperature superconductor? New developments

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Re: A room-temperature superconductor? New developments

#431

Post by distortionfield »

brucethemoose2 wrote: post #187
MillionOClock wrote: post #94

If it's real, how fast could we see concrete applications using this material? 5-year time frame? 10-year time frame? More?

> if you could grow a good single crystal of LK-99, it seems as if the superconductivity might only occur along one crystal axis: put crudely, you'd see superconductivity if you hooked your wires to two particular opposite faces of said crystal, but not to the others! Crystalline grain boundaries are already known to be a big deal in the efficiency of existing superconducting materials, and this would mean that polyc…

But what you just described would still be insanely valuable. Just in the field of semiconductors and chip fab, it would probably unlock insane gains.

Re: A room-temperature superconductor? New developments

#432

Post by derefr »

klysm wrote: post #422
jtchang wrote: post #418

The ramifications of the inflection point we are currently at is mind boggling. I had a hard time explaining this last night but we may very well be witnessing the beginnings of a technological transformation era much like when the p-n junction was invented. From the 1940s standpoint it would be hard to envision all we had today. - Lossless transport of energy - Batteries that don't take any time to recharge - Faster…

> Batteries that don't take any time to recharge Huh? Is this actually a thing that this enables? I don't initially see how

Resistance is what makes things hot, and heat is what makes dumping huge amounts of charge current into batteries a bad idea. No resistance → no heat → no need to charge with low current†.

Another way to say it is that, with a superconducting wire, you can make the wire as thin as you want and still pass the same amount of current through it, without melting the wire. Picture using a USB-C cable to charge your car.

† (There'd still be a current limit due to the heat generated by the chemical reaction that rebuilds the battery's voltage potential... if said reaction is exothermic. Some battery chemistries are endothermic when charging!)

Re: A room-temperature superconductor? New developments

#433

Post by nwiswell »

cperciva wrote: post #416
nwiswell wrote: post #317

Earlier quoted context omitted.

It would be sub-10%* gold content. We're talking about gold doping, specifically substitution in the Pb(1) site, not an alloy. ETA: I was off by an order of magnitude (originally I said sub-1%) because the doping is extensive, and the mass of the lead/gold is a dominant fraction of the total. The formula given in the paper is (subscripts in brackets): Pb[10−x]Cu[x](PO4)[6]O with 0.9 Similarly for Au we would have Pb[…

The superconductor itself would be 7.44% gold, but the wire would probably be much less -- superconducting tape isn't particularly strong so it will probably be wrapped up in layers of insulator and support wires.

I think that's right. There's no indication that it's mechanically strong, so you'd have it wrapped in layers of rubber/epoxy and steel cables in order to suspend it between power poles or transmission pylons.

YBCO tape has a critical current in the 1-10 MA/cm2 range, so if the properties of this RT stuff is anywhere close, the actual superconducting element of the wire could potentially be very thin.

Re: A room-temperature superconductor? New developments

#434

Post by andrepd »

elteto wrote: post #259
hinkley wrote: post #153

Earlier quoted context omitted.

I saw a video the other day that pointed out that the breakdown current for their sample was 260 mA. Now there's a lot of things you can do with 260mA, but I don't believe high-tesla electromagnets are in that list, so no MRIs, no fusion, and probably no electromotive devices (generators, motors).

It took 80 years to go from a crude prototype at Bell Labs to Apple announcing the M1. We just need to know it’s possible. The rest will follow.

I don't get it, is the M1 supposed to be some pinnacle achievement in the history of the integrated circuit lmao

Re: A room-temperature superconductor? New developments

#435

Post by dlivingston »

cududa wrote: post #340
arcticfox wrote: post #218

Earlier quoted context omitted.

There are a ton of them on Twitter.

Yes and many of them are completely wrong. I keep seeing people saying "CPU's that don't generate heat". How exactly would that work? When a transistor turns off/ switches to 0, where does it dump the electrons? Hint: into heat

Sorry, can you explain? My understanding is that transistors don't "dump" electrons anywhere. The gate controls the voltage, which in the `0` state forces resistance to be high enough s.t. current flow through that transistor stops.

As the Veritasium video explains [0], current flow is not a literal flow of electrons, but a state of the electromagnetic field (or something to that effect... it's been many years since my electromagnetism university courses).

[0]: https://youtu.be/bHIhgxav9LY

Re: A room-temperature superconductor? New developments

#436

Post by idontpost »

dragonwriter wrote: post #306
dralley wrote: post #302

Earlier quoted context omitted.

Maybe Venture Capital should spend less money on Juciero, automated pizza ovens, and gig-economy bs and more money on materials science and fusion research. Even if you end up lighting the money on fire, at least it's a more societally productive fire than, say, SoftBank's portfolio.

VC doesn’t put money into research, VC puts money to productization once someone else (ideally for the VCs, government) has paid for research. (Edited to clarify “ideally” parenthetical, in response to a reply that really didn’t deserve to be dead.)

[dead]

Re: A room-temperature superconductor? New developments

#437

Post by araes »

nwiswell wrote: post #317
bufferoverflow wrote: post #295

Earlier quoted context omitted.

People cut cables for copper. Imagine what will happen with cables with gold.

It would be sub-10%* gold content. We're talking about gold doping, specifically substitution in the Pb(1) site, not an alloy. ETA: I was off by an order of magnitude (originally I said sub-1%) because the doping is extensive, and the mass of the lead/gold is a dominant fraction of the total. The formula given in the paper is (subscripts in brackets): Pb[10−x]Cu[x](PO4)[6]O with 0.9 Similarly for Au we would have Pb[…

7.44% gold? That's ~$75 per oz of material. And you're talking about lead cable. Its kind of heavy, even if its thin. And it seems really easy to melt and separate. Notably, most power lines are actually aluminum, which is probably where people would really want this. Also chosen for its low weight / density, cause if you're gonna hang lines 100's of feet long, you want 2700 kg/m3, not 9000 kg/m3, and definitely not 11000 kg/m3. Although probably also significant applications in mm, um, and nm scale wiring.

Re: A room-temperature superconductor? New developments

#438

Post by epistasis »

arcticfox wrote: post #239
deeg wrote: post #165

I'm astounded that the MSM seems to be ignoring this ATM. I did a Google news search on LK-99 and saw nothing from major publications. A search on the NYTimes returned an article from 1974.

I am also completely baffled by this! So many stupid mouse-model medical discovery stories over the years and actually zero LK-99 coverage. It doesn't even matter if it works or not as for whether it's newsworthy; the mystery, human backstory, and Argonne/China/independent scientists jumping to replicate alone is a whole swathe of viable and fascinating topics ready to be published. The crazy thing is NYT just bother…

99% of science journalism is repeating a press release that came out of a university's press office.

It's very hard to become a science journalist where you can pursue your own stories, because the market for this is practically zero in comparison to other parts of the media.

I always try to pay for media that publishes stories from the likes of, say, Ed Yong, and leave messages that I'm doing it for the science journalism. But I doubt it has much substantial effect on how much real science journalism happens.

Re: A room-temperature superconductor? New developments

#439

Post by Workaccount2 »

bluGill wrote: post #414
Workaccount2 wrote: post #304

Earlier quoted context omitted.

All the smart people in the US work in tech and finance. If you have a big ole' brain, why would you take $80k to work in some crumby lab when you can get paid $350k to maintain a login screen from the comfort of your mountain side home.

When you work in a lab you have more ability to work on what you want to. Well at least once you get to the top of the lab - many spend a lifetime working on the interesting problems someone else is interested in but never reach the top where they are in charge. Meanwhile many people who work in tech are able to work on problems they find interesting enough (maybe not the most interesting, but still interesting) and…

Sure if you have a huge drive to work on science directly.

But the fact of that matter is that many people would rather work on something they find interesting enough, while also being able to comfortably afford a good life for themselves and their family.

Re: A room-temperature superconductor? New developments

#440

Post by samstave »

mrandish wrote: post #129

> They also predict that substituting gold atoms into the Pb(1) site could lead to a material with very similar properties, which will be an extremely interesting idea to put to the test. Since the base material is lead apatite, I had a random thought that maybe medieval alchemists trying to turn lead into gold just had it backward, as doping gold into lead might be a breakthrough. :-)

Postulation :

Can someone please take layers of graphene and pure gold leaf and tell me what that may result in, aside from beautiful "damascus"?

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