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Re:Origin of correlated isolated flat bands in LK99 by caesil on Monday July 31, 2023 @11:44PM (#36952029)
Out of curiosity, since this seems like a real inflection point toward trending in that direction, if it becomes increasingly likely that LK-99 or similar material is indeed a high-TC superconductor, what will savvy people be positioning themselves to do? What are good investments? What companies will be started, or what will existing companies be pivoting toward?
Re:Origin of correlated isolated flat bands in LK99 by npunt on Tuesday August 01, 2023 @12:10AM (#36952191)
> What are good investments?

Open-ended research grants to anyone with moderate training in experimental science to just throw shit against the wall and try every last possible combination of something, without concern for 'publish or perish' or jockeying for status in academia. Lets get our smartest and most dedicated technical people back in labs rather than off making CRUD apps for 10x academic wages.

If this discovery is true, we just got lucky. Based on the story we know of LK-99 it almost didn't happen, and our current system is not set up to make these kinds of discoveries quickly. Throwing billions at 'just go find stuff that matters' basic research is ultra cheap in comparison to humanity not having a high-tc superconductor.

Re:Origin of correlated isolated flat bands in LK99 by delfinom on Tuesday August 01, 2023 @06:49AM (#36954506)
I would imagine a lot of discoveries in chemistry that humanity has made were _lucky_ over the course of history.
Re:Origin of correlated isolated flat bands in LK99 by zanderwohl on Tuesday August 01, 2023 @12:25AM (#36952288)
It's going to be a long time before it's put into use if this paper is correct. While it's exciting that a mechanism has been discovered (possibly), it seems to imply that the current method of synthesizing it is partially luck-based, and not very high quality. Of course, if we do understand how it works, lots of people will put lots of research into making a more reliable process, but it's going to take time. I'm not sure a clear path forward exists.
Re:Origin of correlated isolated flat bands in LK99 by petesergeant on Tuesday August 01, 2023 @02:17AM (#36952928)
If it’s shown it’s theoretically possible there’s going to be a gigantic reallocation of resources into productising it and figuring out to make production work. “It’s theoretically possible but hard” is a world of difference away from “unsure if theoretically possible”
Re:Origin of correlated isolated flat bands in LK99 by micromacrofoot on Tuesday August 01, 2023 @10:51AM (#36956694)
I think this is generally true, but also if this is verified it will suddenly have billions of dollars thrown into it overnight... possibly similar to the speed that covid vaccine research was done; there's a TON of money to be made for the first company that can put this discovery to use. This is a once in a lifetime sort of discovery.
Re:Origin of correlated isolated flat bands in LK99 by losteric on Tuesday August 01, 2023 @12:33AM (#36952335)
Posting for Cunningham's law :)

* Green energy suddenly becomes way more viable. Megaprojects in the most efficient sites can send energy long-distance and store it with effectively no loss, somewhat mitigating regional variations (especially if we have a high-trust world order where a united global grid is viable). (I read LK99 might have some limitations carrying lots of current but presumably other approaches would do better)

* EVs: improved performance of motors, batteries, charge time, and weight - huge shift for the market. Much safer than most current car batteries too.

* Big breakthrough for computing in the form of fast, cool, and efficient zero-resistance transistors. Step change for cutting-edge component performance, all the cloud hyperscalers would completely revamp their compute. TSMC / ASML probably get huge volumes of new orders.

Obviously the first bet is following the patents. Otherwise, my play would be the industrial companies that build things that build things, like factory automation companies, followed by companies that would see a surge in demand from products incorporating room-temp superconductor technology, like TSMC, ASML (maybe Apple/AWS).

Re:Origin of correlated isolated flat bands in LK99 by jakeinspace on Tuesday August 01, 2023 @12:41AM (#36952407)
Sorry, but how does one create a transistor from a superconductor? Maybe I’m missing something here.
Re:Origin of correlated isolated flat bands in LK99 by floxy on Tuesday August 01, 2023 @12:57AM (#36952492)
Most superconducting logic families aren't using transistors at all. They use Josephson junctions, which are just two pieces of superconductor separated by a non-supercondutor. RSFQ (Rapid Single Flux Quantum) uses millivolt-high picosecond-long pulses to represent logic 1 and their absence as logic zero, instead of using voltage level as in CMOS.

https://ieeexplore.ieee.org/document/783712 (770 GHz toggle flip-flop in 1999)

https://www.physics.sunysb.edu/Physics/RSFQ/Projects/WhatIs/...

Re:Origin of correlated isolated flat bands in LK99 by Culonavirus on Tuesday August 01, 2023 @01:42AM (#36952746)
Sooo, a 770 GHz processor? Do I understand it correctly? Jesus.
Re:Origin of correlated isolated flat bands in LK99 by yetihehe on Tuesday August 01, 2023 @02:14AM (#36952900)
If using that flip-flop, whole processor will be closer to 100ghz (typically there are multiple transistors which need to stabilise before you have a result of computation). But probably those superconductors could enable even faster transistors and maybe we could get 1THz processors.
Re:Origin of correlated isolated flat bands in LK99 by aitchnyu on Tuesday August 01, 2023 @02:26AM (#36952978)
Like IDE ribbon cables gave way to sleek SATA cables, we could have another parallel to serial transition from silicon multicore crap to superconducting single core.
Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @02:34AM (#36953032)
No, you'll get superconducting multicore because all that will happen is that the bloat will expand to consume the new cycle budget. This has already happened many times.
Re:Origin of correlated isolated flat bands in LK99 by dtx1 on Tuesday August 01, 2023 @06:35AM (#36954436)
I'm looking forward to Chromium version 4201337 needing 20% of my 1Thz CPU to render simple text.
Re:Origin of correlated isolated flat bands in LK99 by regularfry on Tuesday August 01, 2023 @05:58AM (#36954229)
We'll get superconducting multicore because as a first step everyone will just map what they already know to the new space. Which is fun.
Re:Origin of correlated isolated flat bands in LK99 by MayeulC on Tuesday August 01, 2023 @07:25AM (#36954711)
I suspect you'd still need very low temperatures to make this work, even with a high temperature superconductor: low temperatures reduce thermal noise, which may be an issue at such time scales (unless you pump a lot of energy per bit, which means high voltages (limits scaling) or current/capacitances (also limits scaling).
Re:Origin of correlated isolated flat bands in LK99 by jakeinspace on Tuesday August 01, 2023 @08:12AM (#36954999)
Are you aware of any obvious issues with manufacturing Josephson junctions using photolithography? Like, would switching to an LK-99 or similar set us back to the 70s in terms of wafer density/size?
Re:Origin of correlated isolated flat bands in LK99 by floxy on Tuesday August 01, 2023 @10:16AM (#36956224)
You might be interested is this video, which talks about the EDA issues for RSFQ logic:

https://www.youtube.com/watch?v=3O6GpFCIxv0

...and...

https://en.wikipedia.org/wiki/Josephson_junction_count

Re:Origin of correlated isolated flat bands in LK99 by bpye on Tuesday August 01, 2023 @12:47AM (#36952436)
I don’t think we’d necessarily have to use it for transistors, but could use it in place of the metal interconnect that is significant in terms of resistive loss.
Re:Origin of correlated isolated flat bands in LK99 by peyton on Tuesday August 01, 2023 @12:49AM (#36952446)
I think Josephson junctions. Also maybe you could eliminate copper loss by using LK-99 interconnect layers.
Re:Origin of correlated isolated flat bands in LK99 by rezonant on Tuesday August 01, 2023 @02:08AM (#36952872)
Well you can apparently make diodes with them: https://scitechdaily.com/mit-develops-superconducting-device...
Re:Origin of correlated isolated flat bands in LK99 by u320 on Tuesday August 01, 2023 @01:47AM (#36952773)
Transmission losses aren't really a big problem for the grid. Cost, geopolitics, and resiliency matters more. I don't expect superconductors to change much here.
Re:Origin of correlated isolated flat bands in LK99 by bscphil on Tuesday August 01, 2023 @02:06AM (#36952864)
This seemed likely the case to me as well. I'd be interesting in hearing any counterarguments (or better still, actual studies) concerning distribution efficiencies.
Re:Origin of correlated isolated flat bands in LK99 by almostnormal on Tuesday August 01, 2023 @02:52AM (#36953135)
The price for electricity is mainly driven by cost of distribution not production. Reducing losses on distribution would further increase the cost of the expensive part (upgrade to SC net) and decrease the cost of the cheap part.

Storage would help, the cheapest production cannot run continuously.

Re:Origin of correlated isolated flat bands in LK99 by nine_k on Tuesday August 01, 2023 @02:43AM (#36953083)
Transmission losses are a concern because they require building huge, very high-voltage structures.

Superconductors could make transmission lines much more compact, sturdy, weatherproof, and less vulnerable to sabotage. You could run a thick armored cable instead of a set of open-air wires on tall towers.

Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @03:08AM (#36953238)
You would no longer need high voltages at all. We only use those to cut down on those very transmission losses because we're trying to reduce the amount of current. So you can drop all of the step-up-step-down stuff. On the down side: a short is then practically unlimited in current.
Re:Origin of correlated isolated flat bands in LK99 by nine_k on Tuesday August 01, 2023 @03:11AM (#36953251)
Exactly the point.

We will still need some step-downs, because current density is limited. But we will need fewer of them, and they won't need the monumental cooling they have now.

Re:Origin of correlated isolated flat bands in LK99 by leni536 on Tuesday August 01, 2023 @05:14AM (#36954014)
Superconductors have a limit on the current they can carry before the superconducting phase breaks down. This might put similar limits on the voltages.

I agree that the nature of this is entirely different to transmission losses, but I don't expect 230V lines carrying tens of thousands of amps. This would probably require excessive amount of SC material.

Re:Origin of correlated isolated flat bands in LK99 by abdela on Tuesday August 01, 2023 @02:50AM (#36953119)
Exactly, NorNed has an efficiency of 95% https://en.m.wikipedia.org/wiki/NorNed
Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @03:15AM (#36953288)
No, exactly not. The cost of infra is dominated by the transmission network and that transmission network is very expensive to build and maintain, a superconducting network would have some massive advantages. Besides, the losses are in the 5 to 7% range for a typical grid which may sound great in theory but is still a function of the distance between the generators and the consumers. So you can't really put those where you want them, you put them where you have to in order to minimize the transmission losses or you'll have to live with larger losses. Superconductors for the grid would give far more freedom in siting and would allow all kinds of neat tricks such as transporting solar power across the planet based on the day/night and seasonal cycle and likewise for wind power depending on where it is currently blowing the most.

Generating costs are a small fraction of the final price of electricity, taxes and transportation are the big ones.

If you just look at superconductors as a replacement for any old piece of wire you're going to miss out on a whole bunch of advantages, it is a clear qualitative difference which enables solutions that are entirely undoable today. Yes, there is HVDC, but the lines are expensive and due to the high voltages involved are not easy to interface to or from. They do have some unique advantages, being DC they allow non-synchronized grids to be connected.

Re:Origin of correlated isolated flat bands in LK99 by jerf on Tuesday August 01, 2023 @10:42AM (#36956566)
Transmission losses aren't a big problem for the grid precisely because we know we will have transmission losses, so we don't do things that will incur unacceptable losses.

The whole "plate a desert with solar power and solve the world energy problems" doesn't work because the desert isn't where the power draw is. Superconductors hypothetically permit the African desert to supply Europe with power.

As this goes from science to engineering, we may find other issues with that plan, beyond the obvious expenses (for example, current limits can be handled with more wires, but if the current limit is sufficiently small that's still a problem, this is no solution if the superconducting bundle has a hundred square meter crosssection), but superconductors at least put it on the table. Conventional conductors do not.

Re:Origin of correlated isolated flat bands in LK99 by flangola7 on Tuesday August 01, 2023 @10:15AM (#36956213)
Every doctor's office could have an MRI/fMRI machine, brain scans become routine.
Re:Origin of correlated isolated flat bands in LK99 by m3kw9 on Tuesday August 01, 2023 @12:06AM (#36952157)
Depends if this can scale, and can withstand environments and carry enough current density etc.

If it’s brittle as f, then it limits its applications for example.

Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @12:33AM (#36952333)
That's not that important. What is important is that if it is true that this is the first member of a new class of superconductors, a whole new family if you will and that once the principles are better understood materials scientists can go about their search in a smaller parameter space of which they have proof that at least one set yields results.

Compared to the steps that have been happening in the last decades this one would be absolutely incredible in terms of temperature range, if I understood it correctly they aren't even sure about the upper limit due to a restriction in their measuring gear.

Re:Origin of correlated isolated flat bands in LK99 by porphyra on Tuesday August 01, 2023 @01:40AM (#36952737)
On one hand, yes, a new family will be discovered. On the other hand, high temperature superconductors like YBCO are very brittle and it does limit the applications. Traditional liquid helium-cooled superconductors still have to be used in many places.
Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @01:44AM (#36952757)
One of the reasons it is so brittle is because it is still very cold even though it is high temp for a superconductor. Many materials will become brittle when cooled down that far. This is one of things people hope for with higher temp superconductors: that they will be less brittle. But less brittle usually also implies that a material changes shape easier and that in turn may affect the superconductivity. For instance when a large current runs through a superconductor that leads to strong magnetic fields and those strong magnetic fields will actively push against each other trying to destroy the conductor. A non-rigid superconductor would behave in ways that are not really helpful. So there is some chance that all materials that exhibit (useful) superconductivity will end up being somewhat brittle, and will need to be mechanically re-inforced.
Re:Origin of correlated isolated flat bands in LK99 by dtx1 on Tuesday August 01, 2023 @12:13AM (#36952212)
Even if it is, we can coat it in epoxy and deal with it. And even if we can't, remember the first semi-conductor was germanium. If we have a theoretical and practical reproducible RT Superconductor we will very fast find new, better ones.
Re:Origin of correlated isolated flat bands in LK99 by tnecniv on Tuesday August 01, 2023 @12:21AM (#36952263)
And audio nerds everywhere are still lusting after germanium transistors to this day!
Re:Origin of correlated isolated flat bands in LK99 by bick_nyers on Tuesday August 01, 2023 @12:25AM (#36952285)
Could you explain why? Sounds intriguing.
Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @12:33AM (#36952336)
Sounds noisy...
Re:Origin of correlated isolated flat bands in LK99 by Ccecil on Tuesday August 01, 2023 @12:47AM (#36952438)
My understanding is that it is due to the lower voltage drop across the base junction. Germanium is .3v vs Silicon .7v, so with germanium you get less "crossover distortion" when the input signal is crossing the 0 line.

edit: I understand that typically this is biased out with diodes...but the matching is not perfect and it is easier to start with half the distortion.

Re:Origin of correlated isolated flat bands in LK99 by jacquesm on Tuesday August 01, 2023 @12:52AM (#36952469)
Never mind that any half decent amp design biases the base voltage to make sure that you're not going to have that problem.
Re:Origin of correlated isolated flat bands in LK99 by ruined on Tuesday August 01, 2023 @12:51AM (#36952464)
musicians often use them to generate distortion, which is purely an electrical phenomenon. germanium components tend to filter high frequencies and don't clip as sharply as silicon, generating tonal effects that can't really be replicated.

but mostly, a lot of early guitar pedals used germanium components, and so they are associated with prestigious historic guitar players.

here's a video demonstration. silicon first, then halfway through they flip the switches and play the same circuit with germanium components.

https://www.youtube.com/watch?v=W3F8-EAxlXA

Re:Origin of correlated isolated flat bands in LK99 by dtx1 on Tuesday August 01, 2023 @12:57AM (#36952491)
> generating tonal effects that can't really be replicated.

Seems my headphones can replicate it judging from hearing the audio. Am I missing something?

Re:Origin of correlated isolated flat bands in LK99 by piwi on Tuesday August 01, 2023 @01:20AM (#36952629)
There are simulators such a Kemper or neural DSP that can reproduce fairly well any amp, but it is expensive, and imperfect.

When you play on emulation it's difficult to know if it is faithful without having used the original.

Some musician appreciate them, others avoid them.

When you happen to finally get the real gear, you often realize it sounds better, and have a wider range of usage.

The convenience of real dedicate knobs, without menus is unmatched.

There is some pleasure with getting the real thing, and use it by yourself.

Re:Origin of correlated isolated flat bands in LK99 by ruined on Tuesday August 01, 2023 @01:00AM (#36952506)
you're listening to a recording. a musician wants to make sound
Re:Origin of correlated isolated flat bands in LK99 by wahnfrieden on Tuesday August 01, 2023 @01:03AM (#36952519)
Synthesis not sample
Re:Origin of correlated isolated flat bands in LK99 by Blackthorn on Tuesday August 01, 2023 @02:25AM (#36952973)
Well, it's the creation rather than the playback that's important, but you aren't really missing anything. It's not like the various waveshaping functionality of those aren't documented, they're entirely reproducible in software.
Re:Origin of correlated isolated flat bands in LK99 by fennecfoxy on Tuesday August 01, 2023 @06:32AM (#36954417)
This is why most "audiophile" stuff is redundant in my mind, a lot of people seem to act like valves have some sort of magic that we cannot profile and just reproduce in software.

But then again there's nothing wrong with people romanticising stuff as long as it's more "valves are cool because they're retro and nostalgic" over "valves are cool because they're objectively better".

Re:Origin of correlated isolated flat bands in LK99 by tnecniv on Wednesday August 02, 2023 @01:35AM (#36967296)
It’s not about playing the wave form but creating the wave form.

Guitarists today still use tube amps and germanium transistors (in guitar pedals) for two reasons. The first is that most guitar amps back in the day used tubes (mostly) and the early guitar pedals used Germanium. Guitarists wanted to sound like the earlier musicians that used that technology [1] so they want to use that technology to achieve a certain tone with their instrument. The generation after them wanted to sound like them, so that means old tech for them, too! Repeat until today.

The second reason is that an electric guitar is a combination of a physical and electrical system, and the distortion that is essentially synonymous with electric guitars [2] comes from pushing an amplifier out of its “intended” linear regime [3] into the nonlinear regime where it stops amplifying and starts clipping the signal. The way this nonlinear regime varies with the choice of tubes and transistors, but in general you can’t really replicate one with the other. These unique non linearities impact both the output sound and, most importantly to me as a player, the way the amplifier responds to my physical technique (e.g., how the sound varies with how hard I hit a string). I have played solid state amps that aim to emulate tube amps, and to me the biggest difference isn’t the sound but that physical response. I haven’t played the top of the line modeling amps, but this has been my main problem with the practice amps I’ve tried. As a result, if I’m not playing in my bedroom (pushing a tube amp to distort at apartment friendly volumes is hard), I play through a tube amp. The differences between silicon and germanium transistors are similar, but more subtle and I’m someone who owns a lot of pedals and is constantly switching them out to fit my mood.

[1] an interesting counter example is that the Beatles used early solid state amps on at least some albums

[2] Plenty of people play “clean” without distortion, but if you spend time on guitar forums, you see a lot of beginners who ask a question of the form “I just got my first electric guitar, why doesn’t it sound like an electric guitar?”

[3] Early on the goal was to produce high headroom amps that didn’t distort, but this was very challenging. Rock musicians latched on to the distorted sound and then that became a design feature in later amps. However, if you try to make like a 59 Bassman distort, you have to play it loud enough to kill someone. You can also achieve distortion in other ways, e.g. clipping diodes, but that’s not really germane to this discussion.

Re:Origin of correlated isolated flat bands in LK99 by TylerE on Tuesday August 01, 2023 @02:08AM (#36952871)
Also the forward operating voltage of germanium is about half of silicons (0.3V vs 0.7V)
Re:Origin of correlated isolated flat bands in LK99 by ssklash on Tuesday August 01, 2023 @12:51AM (#36952465)
Ge transistors clip audio signals in a "smoother" way. A softer knee, its called.
Re:Origin of correlated isolated flat bands in LK99 by bacon_waffle on Tuesday August 01, 2023 @12:48AM (#36952441)
Hmm, superconducting inductors seem like an audiophile thing. Patent?
Re:Origin of correlated isolated flat bands in LK99 by wiml on Tuesday August 01, 2023 @03:32AM (#36953387)
I've read that superconducting inductors are handy for making very high-Q filters (no parasitic resistance!) and are even used in places as prosaic as cellular towers (LN2-cooled microstrip structures).