Exotic new superconductors delight and confound(quantamagazine.org)
quantamagazine.org
Exotic new superconductors delight and confound
https://www.quantamagazine.org/exotic-new-superconductors-delight-and-confound-20241206/
73 comments
The great thing about watching advances in superconductors is that any day we could discover the first true practical room temp superconductor and that one day changes the world immensely. I personally think we are likely to find one in the next 5-10 years, but that estimate is based on nothing but hope and optimism on my part.
I don't think we need more change right now. We're struggling to make a healthy society with meaning with the leaps in technology of the past 15 years in ML and computing and manufacturing power/ actual power
Better scientific understanding of the underlying process (as highlighted by this article), better pattern detection (AI), and better simulation capabilities (quantum computing) all point to accelerating progress on this front.
What makes me particularly optimistic is the wide range of scenarios in which superconductivity is observed (also highlighted in the article); different mechanisms leading to a similar result suggests much better opportunity for the existence of a room-temp SC than if it were a highly similar pattern.
Certainly such a discovery has some serendipity and luck baked in, but given these advances across the board, 5-10 years seems like a reasonable bet (then another decade or two to widespread adoption). Let's hope we don't blow everything up before then.
What makes me particularly optimistic is the wide range of scenarios in which superconductivity is observed (also highlighted in the article); different mechanisms leading to a similar result suggests much better opportunity for the existence of a room-temp SC than if it were a highly similar pattern.
Certainly such a discovery has some serendipity and luck baked in, but given these advances across the board, 5-10 years seems like a reasonable bet (then another decade or two to widespread adoption). Let's hope we don't blow everything up before then.
From the final paragraph:
_experimentalists are still the ones leading the way. “Everyone’s rushing as fast as they can,” Yankowitz said._
In my experience, the final line is what contributes to my optimism most:
_“I can’t believe that we’re six years in and you can’t take a break.”_
_experimentalists are still the ones leading the way. “Everyone’s rushing as fast as they can,” Yankowitz said._
In my experience, the final line is what contributes to my optimism most:
_“I can’t believe that we’re six years in and you can’t take a break.”_
For the most valuable applications it is also "good enough" to find a superconductor that can be cooled with cheap liquid nitrogen and retain the magnetic field tolerance, current-carrying capacity, and thermal stability of a superconductor cooled with expensive liquid helium.
Some so-called "high temperature" superconductors begin superconducting at liquid-nitrogen temperature or higher. However in real life applications like MRI and particle accelerators it turned out that they still need to be cooled with much colder liquid helium to get the desired magnetic field tolerance, current-carrying capacity etc. Finding a high-quality liquid-nitrogen-grade superconductor with these desired properties would be a revolution in itself.
Some so-called "high temperature" superconductors begin superconducting at liquid-nitrogen temperature or higher. However in real life applications like MRI and particle accelerators it turned out that they still need to be cooled with much colder liquid helium to get the desired magnetic field tolerance, current-carrying capacity etc. Finding a high-quality liquid-nitrogen-grade superconductor with these desired properties would be a revolution in itself.
I know we've got cuprates, superconductors formed with copper oxide, useful up to 133Kelvin, higher than Nitrogen cooling's capability of 77K.
I've read of them being used in wind turbines and particle accelerators, as well as concepts for fusion reactors.
Your comment makes it sound like they have insufficient field tolerance / current characteristics though. I don't think I've heard about Cuprates at all recently.
I've read of them being used in wind turbines and particle accelerators, as well as concepts for fusion reactors.
Your comment makes it sound like they have insufficient field tolerance / current characteristics though. I don't think I've heard about Cuprates at all recently.
Cuprates are also brittle ceramics so they’re difficult to shape and larger pieces and assemblies tend to run into issues with grain boundaries that interfere with superconductivity, so there’s a lot of practical issues. The classic superconductors are very low temperature but are much easier to cast.
There's a few fusion startup companies using superconducting ReBCO tape to make their magnets. From the results that they're getting, I think we've largely cracked the engineering problems of making "wire" from ReBCO and it's largely just a scaling game now. I do want to point out that they're still cooling with liquid hydrogen at ~20K for high current capacity though.
I invested in a couple of fusion startups (because why the hell not?), and the word on the street is that flexible tapes/wires are still not a solved question. Nobody can make them with consistent quality in large enough batches.
>and retain the magnetic field tolerance, current-carrying capacity
Even if it doesn't meet those requirements, room temperature superconductors will have immense value in low-power applications, micro electronics, sensing, etc.
Even if it doesn't meet those requirements, room temperature superconductors will have immense value in low-power applications, micro electronics, sensing, etc.
Data point: liquid nitrogen is cheaper than milk.
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I mean it’s literally selling air :P
How can we take advantage of this to reduce my grocery bill? :)
Mechanical properties are very important, too. Able to bend, able to be cut, able to withstand mild shocks and vibration without fracturing. Something you can make actual wires from, at least at some stage. This, superconducting at liquid nitrogen temperature, would produce a revolution. Transmission lines alone would be huge.
How would we cool transmission lines to liquid nitrogen temperature?
> Transmission lines alone would be huge.
Transmission lines are a great example of competing demands. Copper is a better conductor so why do we use aluminium? Because of weight. And weight is a huge factor in supporting large cables over long distances.
Metals are also ductile, which is important for a cable to hang in gravity under its own weight, be moved by the wind and so on. Assumedly exotic crystals wouldn't have this property. Even if they could, what would the weight be? Would the cross-section need to be much larger? Particular to this family of superconductors, tungsten isn't exactly the easiest thing to do deal with, particularly on a massive scale.
There's an interesting Reddit thread about this topic [1]. One issue it raises is we'd need to essentiaally rebuild our entire infrastructure and transformers are a big part of that.
Personally, I think energy is going to get an awful lot more local. Solar is our future (IMHO). The ability to store excess power generated during the day and then use it when it's dark or cloudy will obviate the need to expensive long-line transmission infrasturcture from distant power plants.
Lastly, the GP is correct: liquid nitrogen is incredibly cheap. It's basically the cost of drinking water. Getting something we could use at liquid nitrogen cooling temperatures would be incredibly impactful.
[1]: https://www.reddit.com/r/AskPhysics/comments/12etlkr/wouldnt...
Transmission lines are a great example of competing demands. Copper is a better conductor so why do we use aluminium? Because of weight. And weight is a huge factor in supporting large cables over long distances.
Metals are also ductile, which is important for a cable to hang in gravity under its own weight, be moved by the wind and so on. Assumedly exotic crystals wouldn't have this property. Even if they could, what would the weight be? Would the cross-section need to be much larger? Particular to this family of superconductors, tungsten isn't exactly the easiest thing to do deal with, particularly on a massive scale.
There's an interesting Reddit thread about this topic [1]. One issue it raises is we'd need to essentiaally rebuild our entire infrastructure and transformers are a big part of that.
Personally, I think energy is going to get an awful lot more local. Solar is our future (IMHO). The ability to store excess power generated during the day and then use it when it's dark or cloudy will obviate the need to expensive long-line transmission infrasturcture from distant power plants.
Lastly, the GP is correct: liquid nitrogen is incredibly cheap. It's basically the cost of drinking water. Getting something we could use at liquid nitrogen cooling temperatures would be incredibly impactful.
[1]: https://www.reddit.com/r/AskPhysics/comments/12etlkr/wouldnt...
Cheaper batteries meeting the storage requirements for renewables would be a game changer!
We're getting that.
https://www.caiso.com/documents/2023-special-report-on-batte...
https://www.caiso.com/documents/2023-special-report-on-batte...
Maybe superconducting transmission lines need to be underground
I suppose that power lines may start looking more like pipelines. These can be above-ground is the actual piping is not heavy, on lower pylons with a reduced span. Liquid nitrogen is lighter than water, does not need high pressure, and the insulation is mostly styrofoam.
The voltage can be substantially lowered, because high currents don't lead to high losses; the current may be made as high as practical, near to the limit of the material's superconducting state.
The voltage can be substantially lowered, because high currents don't lead to high losses; the current may be made as high as practical, near to the limit of the material's superconducting state.
>Lastly, the GP is correct: liquid nitrogen is incredibly cheap. It's basically the cost of drinking water.
Hold on, what? How?? Reaching that temperature seems like a difficult task; and what's used as a source of pure nitrogen, anyway? Is there some clever trick to separating it out from the air?
Hold on, what? How?? Reaching that temperature seems like a difficult task; and what's used as a source of pure nitrogen, anyway? Is there some clever trick to separating it out from the air?
>to get the desired magnetic field tolerance
Interesting, then, that the article actually mentions a superconductor that got stronger in the presence of a magnet! Wild things we're learning here!
Interesting, then, that the article actually mentions a superconductor that got stronger in the presence of a magnet! Wild things we're learning here!
For the most valuable applications, sure - but a lot of the biggest historical advances came not from the first application of that new tech, but from that new tech becoming cheap and ubiquitous.
Maybe (cheap) room-temp superconductors won't actually be that interesting (maybe it just increases energy transmission efficiency 5-10%), but perhaps it's availability catalises a whole range of new applications that were never considered before.
Maybe (cheap) room-temp superconductors won't actually be that interesting (maybe it just increases energy transmission efficiency 5-10%), but perhaps it's availability catalises a whole range of new applications that were never considered before.
If room temperature superconductors existed that were practical for transmission scale wires, it would be possible to make a global superconducting electrical grid. The middle East could fill their desert with solar panels and export that electricity to Europe. The sunny side of the planet could export solar power to the nighttime side of the planet. You could make electrical motors out of it a fraction of the size of current motors, like 1000 of horsepower out of a soda can, which would revolutionize the design of pretty much everything in the world with moving parts. Mechanical transmissions would go the way of the vacuum tube. Any vehicle or ship that's not completely electrified would be hybrid electric at least. You could also miniaturize transformers which has a lot more implications for making everything that uses a lot of power to be much more powerful and cheaper.
I'm not a believer in that timeline. There's a large distance between superconductivity in the lab and commercial application (since you specified "changes the world immensely").
E.g. MRIs still use NiTi (critical temperature of ~10 kelvins), discovered in 1962, for a number of reasons (this is in spite of MgB2 having a critical T of ~39k, ReBCO with a critical T of ~90k, and BSCCO with a critical T of ~108k):
> In this paper, we analyze conductor requirements for commercial MRI magnets beyond traditional NbTi conductors, while avoiding links to a particular magnet configuration or design decisions. Potential conductor candidates include MgB2, ReBCO and BSCCO options. The analysis shows that no MRI-ready non-NbTi conductor is commercially available at the moment. For some conductors, MRI specifications will be difficult to achieve in principle. For others, cost is a key barrier. In some cases, the prospects for developing an MRI-ready conductor are more favorable, but significant developments are still needed. The key needs include the development of... [omitted]
https://pmc.ncbi.nlm.nih.gov/articles/PMC5472374/
Unfortunately, it probably won't be as simple as "step 1 discover material, step 2 manufacture, step 3 profit".
E.g. MRIs still use NiTi (critical temperature of ~10 kelvins), discovered in 1962, for a number of reasons (this is in spite of MgB2 having a critical T of ~39k, ReBCO with a critical T of ~90k, and BSCCO with a critical T of ~108k):
> In this paper, we analyze conductor requirements for commercial MRI magnets beyond traditional NbTi conductors, while avoiding links to a particular magnet configuration or design decisions. Potential conductor candidates include MgB2, ReBCO and BSCCO options. The analysis shows that no MRI-ready non-NbTi conductor is commercially available at the moment. For some conductors, MRI specifications will be difficult to achieve in principle. For others, cost is a key barrier. In some cases, the prospects for developing an MRI-ready conductor are more favorable, but significant developments are still needed. The key needs include the development of... [omitted]
https://pmc.ncbi.nlm.nih.gov/articles/PMC5472374/
Unfortunately, it probably won't be as simple as "step 1 discover material, step 2 manufacture, step 3 profit".
One exciting thing that could still happen in the shorter term (if/when a promising novel "high temperature superconductor" is confirmed) is an explosion of investment into research in the area. So even if it takes decades for Material X to end up in MRI machines, there would still be a steady stream of juicy progress to read about while we wait!
There's some fusion startups successfully making >10T magnets using ReBCO tape now, so hopefully things will scale up/cost down enough to be used in MRIs.
Too soon. I still tear up over LK-99
I'd bet that the first room temperature superconductor does not "change the world immensely."
Resistive losses are just one of very many attributes of a conductor. Others important attributes include:
- current capacity (will you need humongously thick wires to match charge carried by aluminum or copper?)
- ductility (can it be formed into wires cheaply?)
- cost (does CapEx outweigh electricity savings? is it expensive enough that people will cut and steal it?)
- weight (can it hang from power poles? can it be transported on the backs of trucks?)
- temperature sensitivity (does it crack at low temperature? melt at high temperature? change electrical properties depending on the weather? stop conducting on hot days?)
- chemical stability (will it oxidize over a 50-year lifecycle?)
- toxicity (will kids be poisoned if they touch it / eat it?)
- machinability (can it be formed into tiny wires? can it be patterned onto chips?)
- electromigration resistance (will the material break down over time from carrying charge?)
- tensile strength (can it be hung from power poles at their current spacing? would we need to rip out all power poles across the planet? would we need more expensive underground lines?)
- abundance in the Earth's crust (will the price skyrocket if we suddenly need to produce an annual megaton to replace the world's powerlines?)
- geographic concentration (are the primary deposits concentrated in a single country, introducing potential supply chain and geosecurity risks?)
- etc.
It's very likely that the first material which does better on resistivity is going to do worse on these other dimensions. Resistivity is rarely the number one criterion in selecting conductors, from power lines to computer chips.
One of the reason incumbent technologies are difficult to replace is that they win on criteria that are less salient to potential innovators. Aluminum is a common metal for power lines not because it has the lowest resistivity, but because it's by far the best we've got when evaluating this whole portfolio of needs.
Resistive losses are just one of very many attributes of a conductor. Others important attributes include:
- current capacity (will you need humongously thick wires to match charge carried by aluminum or copper?)
- ductility (can it be formed into wires cheaply?)
- cost (does CapEx outweigh electricity savings? is it expensive enough that people will cut and steal it?)
- weight (can it hang from power poles? can it be transported on the backs of trucks?)
- temperature sensitivity (does it crack at low temperature? melt at high temperature? change electrical properties depending on the weather? stop conducting on hot days?)
- chemical stability (will it oxidize over a 50-year lifecycle?)
- toxicity (will kids be poisoned if they touch it / eat it?)
- machinability (can it be formed into tiny wires? can it be patterned onto chips?)
- electromigration resistance (will the material break down over time from carrying charge?)
- tensile strength (can it be hung from power poles at their current spacing? would we need to rip out all power poles across the planet? would we need more expensive underground lines?)
- abundance in the Earth's crust (will the price skyrocket if we suddenly need to produce an annual megaton to replace the world's powerlines?)
- geographic concentration (are the primary deposits concentrated in a single country, introducing potential supply chain and geosecurity risks?)
- etc.
It's very likely that the first material which does better on resistivity is going to do worse on these other dimensions. Resistivity is rarely the number one criterion in selecting conductors, from power lines to computer chips.
One of the reason incumbent technologies are difficult to replace is that they win on criteria that are less salient to potential innovators. Aluminum is a common metal for power lines not because it has the lowest resistivity, but because it's by far the best we've got when evaluating this whole portfolio of needs.
Well lots of these limit the applications but something could have these limitations and still be a commercial success in some valuable niche fields.
I think even if it's only usable in niche scenarios it would still be a commercial success. Superconductors are useful even when they're hard to use, as seen with existing cold temperature superconductors which a room temperature one could certainly replace and become a commercial success in doing so. With that said, you're likely correct that the first attempt won't catch on for mass adoption.
> as seen with existing cold temperature superconductors which a room temperature one could certainly replace and become a commercial success in doing so.
High temperature superconductors are only seeing commercial use in the last few years (after their discovery in the 80s) due to issues like poor ductility.
High temperature superconductors are only seeing commercial use in the last few years (after their discovery in the 80s) due to issues like poor ductility.
Electromagnets.
Why is room temperature important, what if "the world's first superconductor at 0C" was the headline?
I agree, 'room temp' isn't exactly precise. Even if it could work at 'room temp' if it didn't work just above that it would be too finicky for a lot of applications. Somewhere around there is likely the 'magic' point for a huge number of applications that will change the world. The perfect would be, of course, one with a very broad range of environments it could perform in. I think we are on track to figure out how to make something truly sci-fi in its properties: Strong, wide range of temp/conditions, flexible, etc etc. Once we get the theory perfect I bet the world will really open up.
I don't think room temperature is important per se. Rather it's shorthand for a superconductor that functions without special cooling. Even if the temperature range is somewhat limited, it's still possible to be pretty useful (e.g. deep ocean temps are fairly cold and stable so a superconducting cable to power repeaters on fiber optic cables might be useful).
Is their existence just speculation or is there mathematical / empirical observations that suggest they exist we just don’t know about them? Is it guaranteed, or highly likely, that one exists we just haven’t found it?
I don't think we'll really see a superconductor that ticks all the boxes.
Reality is too noisy for such effects to take hold. If there was I think evolution would have already used it by now.
Reality is too noisy for such effects to take hold. If there was I think evolution would have already used it by now.
Do you mean biological evolution? There are a vast number of useful materials that terrestrial organisms cannot evolve because they're incompatible with the chemical/physical conditions inside living things. Organisms never evolved the use of aluminum structures, for example, even though aluminum has many useful properties and is more terrestrially abundant than carbon.
High temperature superconductor could in principle be inside an organism, because it's not fixed to a specific element. And energy savings would be immense.
One thing that goes unmentioned about room temperature superconductors is that they store energy as well. U = (B2/(2u0))V. 2u0 is about 2.5E-6N/A2
So a 1m3 7T magnetic field would be about 20MJ or 7KWh. That doesn't sound like much, but collapse times could be microsec to generate GW of EM.
So a 1m3 7T magnetic field would be about 20MJ or 7KWh. That doesn't sound like much, but collapse times could be microsec to generate GW of EM.
This is a useful fact to have handy.
Commercial MRI quenching doesn't result in explosions and there's 7T research MRIs so I assume the issue with how to bleed off energy is solved in a safe enough manner already
These novel new superconductors are generally considered to be "bad superconductors." They have really low critical fields.
Wow. Go over to [1] and read the papers. This is good stuff. When someone finds new physics, interesting things result.
Tungsten disulfide/boron nitride superconductors? That's a new direction.
This article describes a new research result as a new research result, not as "trillion dollar industry by 2027". That helps credibility.
[1] https://physics.mit.edu/faculty/long-ju/
Tungsten disulfide/boron nitride superconductors? That's a new direction.
This article describes a new research result as a new research result, not as "trillion dollar industry by 2027". That helps credibility.
[1] https://physics.mit.edu/faculty/long-ju/
>This article describes a new research result as a new research result, not as "trillion dollar industry by 2027".
I don't like that language either, but it may be wise to understand that different audiences are reading this, and it may be effective for the author to reach the others in this way. And besides, in general it's easier for a rationalist to ignore such language than it is for an industrialist to add it.
I don't like that language either, but it may be wise to understand that different audiences are reading this, and it may be effective for the author to reach the others in this way. And besides, in general it's easier for a rationalist to ignore such language than it is for an industrialist to add it.
Bollocks. "Hype language" has a very strong correlation with people who don't know what they're talking about. (Probably because most people who use it do not, in fact, know what they're talking about, even if some might.) So other experts in the field will look down on you if you speak like a British university press release.
I agree with you. I just think it is wasted effort to complain about the quality of press releases. I am consigned to their poor quality, and my solution is to read primary sources.
As someone who knows nothing about this, how is something like "Tungsten disulfide/boron nitride" selected? Is it based on some models? Or, is it more of a random walk?
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They are choosing from a subset of materials that can form stable 2D crystals in order to test effects of relative twist angles on their energy bands.
They're two materials that 2D materials people commonly stock. BN is thought to be a pretty innocuous insulator. Might as well be the lettuce of the sandwich. However, it's now showing that it has effects on the nearby layers, so people are playing with it in heterobilayer devices.
A large part of the field of 2D materials is just trying stuff.
A large part of the field of 2D materials is just trying stuff.
otoh, "a graphene device produced a mythical form of superconductivity"
:)
:)
room temperature superconductors are inevitable, all matter is conductive and photo active in some way or another,and conduction is one of the non optional components of reality, so the number of possible compounds that might superconduct is huge
and now that there apear to be multiple mechanisms
that superconduction can function from, means that the search will begin in earnist
its a multi trillion dollar app
Is a 400C superconductor also inevitable?
Given enough pressure it already exists!
Why is it inevitable? Is there some physics principle that proves they should exist even they're beyond current scientific knowledge?
Question - is this a field ripe for breakthroughs using advancing AI capabilities? Or not likely because LLMs haven’t ingested much data that could help reason in this field (or whatever reason)?
traditional LLMs do not reason
Could this "reality search" stuff be parallelized?
Could reaction permutation and property testing occur in a more automated fashion than is currently?
Could reaction permutation and property testing occur in a more automated fashion than is currently?
I wish all the smart physicists were working on this instead of string theory.
Why not both? We need people working on moonshots in hope of a breakthrough that will leap us forward. Even if, in case of string theory, we probably both agree that the chance is slim at this point (but I'm not a physicist, so nobody asked my opinion and nobody should listen to it).
I worked in Cory Deans lab when he did a brief professorship at City College. He is the most sharply intelligent person I have ever worked with, a savage experimentalist always devising new ways to experiment in nanofabrication and his theoretical curiosity is boundless. Additionally, he’s a really nice Canadian when he goes to the pub!
If you ever wonder why these products using graphene aren’t commercially viable, it is insanely difficult to work with and prepare. Imagine trying to make a sandwich that’s 5x5 microns in area and about 2-3nm thick. Graphene is essentially atomic tissue paper subject to all sorts of contamination and small scale effects.
If you ever wonder why these products using graphene aren’t commercially viable, it is insanely difficult to work with and prepare. Imagine trying to make a sandwich that’s 5x5 microns in area and about 2-3nm thick. Graphene is essentially atomic tissue paper subject to all sorts of contamination and small scale effects.
Fascinating stuff. Though it puzzles me that some of these exotic superconductors have been known to us for years yet there’s not been much progress (esp the one with graphene sheets, with a 1 degree tilt). Is that because they are just so hard to synthesize? What would it take to get to the next stage?
I came across another technique discovered many years ago, where they used scotch tape to alter the physical configuration of the material to make it superconduct. At room temperature, I believe.
This all sounds very ground breaking to me, yet we don’t hear about any big co doing any work on them.
I came across another technique discovered many years ago, where they used scotch tape to alter the physical configuration of the material to make it superconduct. At room temperature, I believe.
This all sounds very ground breaking to me, yet we don’t hear about any big co doing any work on them.