10 ms·
Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical cur
by andreiklochko 3y ago
Guys, even if everything in this paper is true, the material as it is might have limited applications.
From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current density, not just current which is meaningless (and around 300 mA).
This means you can't actually push big current through this thing (yet). You can't make a powerful magnet, and you can't make viable power lines, both applications that were the hallmark of "room temperature superconductor revolution".
Of course, maybe one or a few more tweak(s) of the material and boom, it will give high J_c and B_c. I really hope it does, it would be super cool!
- JumpCrisscross 3y ago> the material as it is might have limited applications Is LK-99 part of a larger (either known or emerging) class of materials? I'm not understanding what the lead and copper ions are doing to create internal stress, and why that leads to superconductivity.
- jacquesm 3y agoJust like in previous super conductor findings once a material is made and understood that usually paves the way to new discoveries, sometimes those are (big) improvements on the status quo. I'd expect this finding - assuming it is true and verified - to result in massive funding towards the material science labs to try to improve on it. So I'd say this is example '1' of a new class of materials and if it holds up then probably we will find more members of that class once the mechanisms are understood.
- deckar01 3y agoPb(2)-phosphate is a crystalline compound. They are creating a 2D film of it using vapor deposition, then doping it with copper ions. This is a standard process in semiconductor manufacturing. There are room temperature ambient pressure materials doped to create quantum wells in production right now. They are not super conductors, because the quantum wells are merely impurities that reduce the resistance of the material. I believe this paper is claiming a crystal so saturated with quantum wells that it conducts primarily through quantum wells with almost no resistance (and that all of the other physical properties of a superconductor arise from this).
- nvlstc 3y agoMaking qp9 to 30 degree
- thehappypm 3y agoThey've just proven (if true of course) that it's possible at all. That is a massive, massive leap. And once it's possible, it won't be long until it's optimized. We've seen this everywhere -- transistors were once huge and now nanometers; solar cells have improved in every where; batteries are cheaper and better than ever.
- pohl 3y agoI was with you on the first part. If this proves room-temperature/ambient-pressure is possible at all, that is huge. Not so sure about the "won't be long until it's optimized," though. There are a lot of examples where something seems perpetually 20 years away. I'd advise tempering the transistor-based optimism with just a skosh of fusion energy skepticism.
- jacquesm 3y agoCompared to fusion it should be a lot simpler and if there is one material that exhbits these properties there might be more. I'm really hoping this isn't a scam and that there isn't some kind of critical error. Regardless of how much more work needs to be done to get this to commercially viable at scale if true I would imagine that massive investment will start chasing that goal. Just thinking about the possible applications for storage makes me dizzy. Fingers crossed.
- serf 3y ago>There are a lot of examples where something seems perpetually 20 years away. I'd advise tempering the transistor-based optimism with just a skosh of fusion energy skepticism. most of the common examples are in-the-works or exist in some form, they just don't satisfy the 'every-person' checkbox yet. AI? sure. Flying cars? sure. Robots? sure. Fusion is in the works, too. Tens of billions of dollars being thrown into the ring by private capital -- and recently -- which is a pretty good indicator of 'perceived realistic' historically. Also, it's kind of apples/oranges. We had equivalent mechanisms before the transistor, transistors just lead to extreme miniaturization of logic gates that we now enjoy. Fusion energy production doesn't (really) have that equivalent. similarly : room temperature atmospheric pressure superconductors are a new thing if proven possible.
- CamperBob2 3y agoThat's the D part. This is just the R part.
- fabian2k 3y agoJust for comparison, an typical MRI magnet is 1.5 Tesla. An NMR spectrometer can go up to 28 Tesla (using new high-temperature superconductors). The LHC magnets are around 8 Tesla. Those are the kinds of magnetic fields the classic superconductors and the newer high-temperature superconductors can achieve.
- WithinReason 3y agoIt would be super cool, without being supercool
- rezonant 3y agoor superhot for that matter!
- baq 3y agoCan you make wires in chips out of this? MRIs are nice but maybe zero resistance between transistors on my phone’s cpu is cool, too?
- mcv 3y agoCPUs that don't generate heat? That would be pretty awesome.
- nick__m 3y agoSuperconductivity is not enough for a cpu that doesn't generate heat, you would need a cpu built of reversible logic gate. Thermodynamics requires that when you destroy a bit of information you generate at least 2.9×10−21 J. It's the Landauer's principle.
- arjvik 3y agoSay we use this (or any other) superconductor to build an AND gate. Assume one input is zero, so the information of the other input is lost. I assume the energy lost as heat occurs due to the "current" going into the and gate having "nowhere else to go" other than to dissapate as heat? If that's the case, simply redesigning our logic gates to have as many outputs as they have inputs, with some of these outputs feeding indirectly back to the power source without being read, seems feasible.
- ChadNauseam 3y ago> I assume the energy lost as heat occurs due to the "current" going into the and gate having "nowhere else to go" other than to dissapate as heat? Not quite, it's a thermodynamic principle that applies to any way you could possibly compute AND. Basically, the laws of physics are reversible, so your computation must be reversible too. There are 4 possible inputs to an AND gate, so to be reversible there must be 4 possible outputs, one for each input. But we only want one output for the rest of our computation, so the other one dump into the environment somehow.
- z3t4 3y agoIm thinking transportation pipelines for small packages. A superconduction railway inside a vacum tube.
- zerealshadowban 3y agostep forward for hyperloop-like transports
- ReptileMan 3y agoOne miracle at a time.
- jacquesm 3y agoThis is a dancing pig. The thing to appreciate is not how well it dances but that it dances at all.
- paulddraper 3y agoHahaha perfect analogy
- m463 3y agohttps://xkcd.com/2798/ https://xkcd.com/2798/
- mabbo 3y agoThis is one of those lines that sounds like it came from a book of quotations, but I can't seem to find any source beyond this post.
- Name_Chawps 3y agoI've heard it as: It's like a dog riding a skateboard. It's not impressive how well it rides, it's impressive that it rides at all. But I can't find the original source or anything.
- beambot 3y agoRiff on this: When your product is a monkey reciting Shakespeare while standing on a box in Central Park, you don't start by building the box.
- jacquesm 3y agoThat's funny! I think I may have been guilty of box building a couple of times. Nice boxes... but still... no monkey.
- inasio 3y agoNo wireless. Less space than a Nomad. Lame
- remote_phone 3y agoI genuinely hate responses like this. For some reason, there’s a contingent of people that think that by poking holes and pooh-poohing things, it gives them clout. It happens far too often in tech and I hate it. Look how often the post has “can’t” or “couldn’t”. Instead of giving reasons why something sucks, how about being supportive and talking about why it’s awesome and what possibilities this opens up?
- rezonant 3y agoI generally agree but the post in question isn't a strong or extreme example of this. The only thing that irked me was the "Guys," part
- Meegul 3y agoI don't think OP is being overly negative in relation to the tone of the rest of the comments here. Nobody else up until this comment had mentioned anything about the actual important performance characteristics that the paper's authors' are claiming, and this does put it into perspective with the current state of the art. And OP does even end on an optimistic note anyway. No need to resort to personal attacks. Edit: I appreciate you toning down the more combative part of your comment.
- dotnet00 3y agoWhile I often agree that the tone on these kinds of posts on HN is often annoyingly and unproductively cynical, I think him just pointing out the current limitations of the result is not that much of a problem. It isn't like he's making the overused "perpetually 20 years away" joke about potentially revolutionary technologies.
- opwieurposiu 3y agoYou can improve the current density a lot if you can make a single crystal, or at least make your crystal grains larger. Impure superconductor samples often come out as a spongy mixture of superconducting and non-superconducting bits, the critical current is limited because less then 25% of the cross section is actually carrying current. When I was DIYing YBCO this is what happened most of the time. Every now and then you would get a good one. See this patent for growing single crystals of YBCO. https://patents.google.com/patent/US6046139A/en https://patents.google.com/patent/US6046139A/en edit: Actually if you look at the sample picture in the paper on page 7, it looks like spongy crap. Nobel prize winning spongy crap, but still. I would expect the numbers to improve as better crystal growing methods are found.
- techdragon 3y agoYeah, it’s been a pretty solid trend line, new superconductor, first batch is usually kinda shitty, but proves the basics, refining the mix nails down its exact performance characteristics. It’s spongy grainy crap indeed… but as long as their analysis holds up to scrutiny and replication… and whoa boy do I bet there are people already trying to replicate this result as I’m typing my reply and reading the rest of the comments…. As long as the results hold up and this isn’t an abnormally low performing superconductor… i have no doubt this is going to win a Nobel prize. This has been the prize for a long time in this whole discipline, and they may have finally nailed it. We as a species may be on the bring of a revolutionary step forward in what we can achieve in engineering and science. Better instruments and more powerful or sophisticated motors and power systems. It’s heady stuff to think it may happen in my lifetime.
- justahuman74 3y agoAs someone who doesn't follow superconductors, what sorts of things about life/engineering/society would change, how dramatic would it be, and more importantly: which stocks would you pick :)
- zamalek 3y agoThe changes would be more dramatic than the discovery of fire, but would occur gradually.
- TaylorAlexander 3y agoHow powerful is the magnetic field in typical brushless motor? Even if it can’t be used for an MRI machine, it could do wonders for efficient (and/or compact) robotics and electric vehicles. I’m also very curious what kind of inductors you could make for switching power supplies using superconductors.
- mildchalupa 3y ago1.5-2 Tesla you hit the knee of the BH curve and you saturate the steel.
- eternityforest 3y agoDo you need steel? What about a brushed(Assume some fancy future micrometer gallium filled gap that doesn't wear or something) motor that just has superconducting coils attracting each other?
- TaylorAlexander 3y agoYeah I guess if you have superconductors you prob don’t need steel. Bonus, no cogging.
- HackOfAllTrades 3y agoCan't wait to replace all the resistors in my PSU with SuperConducting Resistors. :-)
- gerdesj 3y agoWhen I were a lad ... I remember the first superconductors (long predicted) being announced in the mid '80s. They stayed high on the nerdy headlines for quite a few years. Excitable write ups in New Scientist for us civilians. Nuclear fusion was still 50 years off but room temp superconductors were only a few years off (nope). I went to a posh school in Oxfordshire in the mid to late '80s and my physics class (form) had a field trip to Culham and also a double lesson/lecture done by a handful of Culham physicists back in school. I am very aware of what a privilege that was. Now I'm 53 and been around the block a bit, I really appreciate how time is required for some things. A lot of time.
- jacquesm 3y agoVery true. I remember cheering since the mid 80's every time the temperature for superconductivity went up, sometimes with 20 degrees K in one go. And then it was quiet for a long long time with a plateau. More recently, two major jumps, the last one of > 50 degrees (2017, H2S), and now this... https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.201705321 https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002...
- gerdesj 3y agoI've forgotten how many times one of the most important thresholds in our times has been bumped up a bit. Now we seem to be offered heaven on a plate. If superconductance can be reliably demonstrated at RTP (you wear a light cotton shirt, instead of 1cm thick fancy weaves involving an awful lot of rubber) then we are laughing all the way to ameliorating climate change. Even if this result is confirmed then I think it will take at least 20 years to dig in to reversing climate change. We live in unpleasant times.
- dTal 3y agoIf the argument is that superconductivity = better efficiency = less energy use, then I am afraid that Jevon's Paradox has some bad news: https://en.wikipedia.org/wiki/Jevons_paradox https://en.wikipedia.org/wiki/Jevons_paradox
- freeone3000 3y agoCould we, for example, make circuit traces out of it?
- jacquesm 3y agoYou could probably do that but it wouldn't be a whole lot better than the existing traces: it's not usually the resistance that limits the size of circuit traces but the mechanical requirements, such as your ability to connect to them and to space them apart so you don't get crosstalk due to capacitive or inductive coupling. If you could use it to make circuits, especially of a high level of integration then it might well be something much more interesting (Josephson tunneling is briefly mentioned in the article). That could theoretically give rise to very efficient switching gear and if it can be miniaturized enough to efficient CPUs and memory. This is because the typical transistor uses power mostly in the time between the transition between the 'on' state and the 'off' state, when it is acting as a resistor. If you could get rid of that resistance during the transition then you might be able to reduce the amount of power a given circuit uses, but there are still lower limits off losses that you won't be able to escape, so it will not make your CPU magically use zero energy. Given the contents of the paper such applications are a very long way off and may in fact never happen. Let's first see (1) if it is true and (2) if it is true how well it stacks up against copper wire of the same diameter and commercially available super conductors in terms of cost and practical current carrying capability. If that's all good then this will really be a game changer.
- TaylorAlexander 3y agoSometimes the resistance of the trace matters. I’m designing a motor controller that needs to carry 100 amps and the resistance of the copper means that large planes are needed to carry the current without overheating. Beyond that I agree with everything you’re saying.
- jacquesm 3y agoThat's absolutely true, in power electronics there are applications where the current carrying capability of the traces really matters. Typically you'd either use a very wide trace or some other trick such as via'ing together multiple layers of traces or even to tin-plate the trace. In extreme cases I've seen traces reinforced with solid copper bars. There is also extra thick copper clad board ('heavy copper PCBs').
- PBnFlash 3y agoEven application in antenna would be revolutionary
- mirekrusin 3y agoCan you make efficient chips with it?
- mikewarot 3y agoI'd use it for making my own SQUIDs[1], as a start. There are a number of experiments I want to do, and things I want to understand[2][3], and not having to have cryogenics keeping the detectors cold would be helpful. I'd also like to use this for antennas, transmission lines, and tuned cavities.[4] There are a lot of things you could do at VLF frequencies[5] that require long, long wires... with lots of resistance, unless you have a defense budget, the resistance eats into efficiency. Superconductors could help deal with that. [1] https://en.wikipedia.org/wiki/SQUID https://en.wikipedia.org/wiki/SQUID [2] https://en.wikipedia.org/wiki/Aharonov%E2%80%93Bohm_effect https://en.wikipedia.org/wiki/Aharonov%E2%80%93Bohm_effect [3] https://en.wikipedia.org/wiki/Longitudinal_wave#Electromagnetics https://en.wikipedia.org/wiki/Longitudinal_wave#Electromagne... [4] https://en.wikipedia.org/wiki/Superconducting_radio_frequency https://en.wikipedia.org/wiki/Superconducting_radio_frequenc... [5] https://en.wikipedia.org/wiki/Very_low_frequency#Amateur_use https://en.wikipedia.org/wiki/Very_low_frequency#Amateur_use
- King-Aaron 3y ago> it would be super cool It would be super room temperature
- Brian_K_White 3y agoIt would be super room temp. I don't apologize.
- deleted 3y ago[deleted]
- Gud 3y agoI mean, come on. It's still a fantastic achievement! No one is expecting fusion magnets and 10kA power lines from this tomorrow!