TechStuff Tidbits: Superconductivity and LK-99

Or it's possible we could just be waiting to find out that a promising experiment isn't really what we thought it was. And this all centers around super conductivity. Now, to understand super conductivity, we first have to talk about just plain old conductivity the Clark Kent super Conductivity's cal l and we're specifically talking about electrical conductivity rather than thermal conductctivity for this episode. So we say a material is conductive if it is well suited to allow an

electric charge to pass through it. Materials that resist electrical charges passing through them are insulators. In Between conductors and insulators, you've got your semiconductors, which can behave like a conductor under certain conditions and like a resistor under others. So a good conductor will allow electric charge through pretty easily, but some of that energy in that electrical charge will

end up converting into heat and you lose that. This is because even good conductors like copper still have some electrical resistance. You can actually affect the amount of electrical resistance by changing the physical properties of the copper itself. For example, a very thin copper wire will have higher electrical resistance than a thick copper cable. It's made out of the same stuff, but the actual physical properties change things,

but it still will have electrical resistance either way. And some of our appliances, like say toasters, they rely on electrical resistance. We purposefully build them so that they have these metal coils inside that heat up as we pass an electrical current through them, and that ends up toasting your bread. The electrical resistance causes some of the charge to convert into heat, so then you can toast your

toast and make your belts or whatever. Resistance means that it is impossible for us to build a perfectly efficient electrical system under what I would call normal circumstances, like every day type circumstances and very very specific circumstances, we can achieve it, but it is a lot of work and we'll get there. But under normal circumstances, we're always going to lose some energy due to electrical resistance. You know,

it's going to boil off heat. And this is why lead gamers out there have to invest in really effective cooling systems for their gaming rigs. Sometimes they get those like crazy water cooling systems. The over clockers out there might even play with like liquid nitrogen for usually an exhibition type thing. It's not something they would do for every day, but yeah, they have to deal with that

because their gaming rigs have countless circuits in them. Like when you think of a CPU or a GPU, you know, central processing unit or graphics processing unit. Essentially those are chips with just millions or billions of little circuits in them, and if you don't take the heat away from those circuits, then it's going to overheat and stuff is going to wear out, it's going to go wrong, it's gonna shut down. So you have to have a way to manage the

heat in the system. And that's why you've got these these great cooling systems and these gaming rigs and other types of computers. So under normal circumstances, an electrical can we'll serve as a pathway for electricity. But you aren't going to get the same amount of electricity out as you put into it. There's always going to be less electricity coming out the other side because of the fact you lose some of it due to heat. Unless and this is where we have to go back in time.

In fact, I don't think we've used the tech stuff time machine in a few years. Looks like I still got it over there in the corner. It's holding one of my guitars. Let me just just move that up. Oh it's okay, right there, we go and get in and all right, let's set the dial to nineteen eleven. Here we go. Okay, we're in nineteen eleven, and here we see a Dutch physicist. His name is Oh no, okay,

I'm going to get this totally wrong. Just saying it right up front, I cannot pronounce Dutch names, but I'm going to give it a try. Just know that this is not the right pronunciation, and I understand, and I know it's terrible. You don't have to tell me anyway. Haika common link on us and he's leading a research team and they're studying the effects of very very cold temperatures on electrical conductivity, I mean, like exceedingly cold temperatures.

So his team is currently cooling a sample of mercury to minus two sixty nine degrees celsius. That's four point two kelvin, so we're not that much higher than absolute zero, like the temperature of deep space. And his team is now observing that at this temperature, mercury's resistance drops to zero. It no longer has electrical resistance. It has become a

perfectly efficient conductor for electricity, a superconductor. And it turns out that below a specific critical temperature, and that temperature depends upon the material that we're using at the time, the conductor will go through a fundamental change that means they no longer offer resistance to electrical charges. Why, well, that's a darn good question to answer that. Let's get back to present day. All right, everyone back in the

time machine. Here we go. Oh it's hotter than I remember. Okay, Well, now here we are. So our understanding of physics at the time of this discovery of superconductivity had no explanation as to why this would happen, or how it happens, or in fact, even what was happening on a granular level. I mean, we knew that resistance was dropping to zero, but he didn't know what was happening to cause that. Even quantum theory shrugged and said, beats me, daddy, Oh,

I got no idea. It would actually take a few decades before some researchers proposed a hypothesis regarding what was going on. And well, their hypothesis, while good, doesn't cover everything, but anyway, between nineteen eleven and nineteen fifty seven. Nineteen fifty seven is when we would get that hypothesis. There was another discovery relating to superconductivity that was really neat.

Two German scientists, Walter Meisner and Robert Oxenfeld found that when a conductor was cooled to that superconductor state, when it dropped below its critical temperature, it would also expel magnetic fields. So we've talked a lot about electromagnetism in this podcast. Right, If you pass a conductive material through a magnetic field, the magnetic field induces current to flow through the conductor. What allows us to make things like

electrical transformers. In alternating current transmission. We also know that an electric charge moving through a conductor generates a magnetic field. I mean, I'm sure everyone out there has done some version of the physics experiment where you take copper wire and you wind it around an iron nail, and you connect the wire to a battery, and now you've got yourself an electromagnet. So there's this beautiful relationship between electricity and magnetism that we've been studying for more than a

century now. Well, with superconductors, Meisner and Oxenfeld observed that nearly all internal magnetic fields that should be passing through the superconductor material were zeroed out. They didn't exist. The exterior magnetic field intensified. So it turns out that the magnetic fields that normally would be able to pass through

the superconductor material were now being expelled. They were passing around it as if the superconductor had some kind of force field against magnetic fields being able to penetrate it. Similar to how electricity can't get out of a superconductor, you know, it doesn't boil off in the form of heat, magnetic fields can't get into a superconductor under normal conditions. We'll actually talk a bit about the limitations of that in just a moment. Now, one super interesting thing about

the so called Meisner effect. Now some folks will actually include Oxenfeld and call it the Meisner Oxenfeld effect, But more often than not, I just see the Meisner effect, which is, you know, just shows that you really want that top billing. Anyway, One really interesting thing happens when you bring a permanent magnet near a superconductor that then is brought to below its critical temperature. So normally the magnetic fields that are emitted by the permanent magnet would

also then pass through the superconductor once the magnet's close enough. So, if you have a superconductor of material but you haven't cooled it below its critical temperature, it's not acting as a superconductor yet. You could put a physical magnet right on top of that. Then, if you cool the superconductor material so that it does go below its critical temperature, it starts to expel magnetic fields. Well, the permanent magnet is generating a magnetic field that otherwise would be passing

through the superconductor. Since the superconnector is expelling the magnetic fields, it pushes against the permanent magnet, and the permanent magnet will levitate and appear to really lock in place above the superconductive material. You could also lay this out so that you had say, electromagnetic track on the underside of a table and take a puck of superconductor material that's cooled below its critical temperature and lock it in place

below the electro magnet. That's possible too, I've seen that. But it looks really cool because it looks like it's just magically hanging there in the air, and you can change its orientation and it will maintain that orientation above the superconductor material. Now there's a lot that's going on here. It's not just like magic. In fact, it's not magic

at all. But the explanation gets really tricky. There's like kind of like little currents, like a little eddy within the superconductor that's effectively creating a magnetic field that matches but repels the permanent magnets field. No matter what orientation you put it in. You change the orientation of the magnet, the little eddies, which are really little currents of electrons in the superconductor material change and then it continues to

repel the magnet perfectly. This, to get more specific, would get into quantum mechanics, and I would just goof that up if I were to attempt to explain it, because it is well beyond my understanding. So I will say that if you haven't watched any videos of magnets interacting with superconductors or vice versa, you should really check that out. There are a ton of them on YouTube. They are

really fascinating to watch. It looks at first like you're watching some sort of camera trickery because the materials are behaving in a way that's counterintuitive. We don't see stuff like that in our day to day lives. It's really interesting. And the fact that you can position the magnet in different orientations with regard to the superconductor and it will just stay in that position relative to the superconductor as if it's locked in space. It's really remarkable. Okay, we're

going to take a quick break. When we come back, I'm going to talk about that hypothesis I alluded to earlier and how it attempted to explain what was going on. But first, let's thank our sponsors. All Right, we're back, and now we're getting up to the nineteen fifties and a trio of American scientists John Bardeen, Leon Cooper, and John Shreefer proposed a microscopic theory of super conductivity, and it became known as the BCS theory. It took the

first letter off of each scientist's last name. The theory has to do with electron pairs and crystalline lattices within the superconductor and these vibrations called phonons. And I can't really pretend to fully understand it, or even partly understand it, but it does a good job of describing what's happening

for super cooled superconductive materials. However, this particular hypothesis or theory did not explain how this would work with superconductors that could operate at so called high temperatures, you know, beyond a threshold. This theory doesn't really apply. And the problem is we were observing effects that went beyond the parameters this theory would cover. Now, when I say high temperature, I'm not actually talking about anything that you or I

would consider a high temperature. In fact, it's quite the contrary. We're still talking temperatures that can get down to as low as almost minus two hundred degrees celsius. To date, I want to say that the hottest superconductor that ever operated is still like around minus twenty five celsius something like that, and even then it's under intense pressure. We'll talk about pressure too, so you know, we're really talking

about very, very very cold temperatures. Even with the so called high temperature superconductors, it's just that they're much higher than say minus two hundred and sixty nine celsius. Until very recently, all claims of finding material that displays super conductivity at temperatures that we would even remotely consider comfortable

have all fallen through. Right Like, scientists would submit a paper suggesting that they had made a breakthrough and found such a material, and then later retract those papers, discovering that, in fact, there was some sort of mistake along the way and they were not correct, and so they had to, you know, take it back. Now. Interestingly, two factors can potentially destroy the superconductor's state, and one we've already mentioned

is temperature. Right if the temperature goes above the critical temperature for superconductors, then the material loses superconductivity. They will again have electrical resistance, it will no longer expel magnetic fields. But the other factor that can disrupt the superconductor state would be a sufficiently powerful magnetic field. I mentioned, like a regular permanent magnet on top of a superconductor. You'll

see the permanent magnet levitate. Well, if that permanent magnet was super strong, like it really had very strong magnetic fields, then that could be more than what the force field the superconductor generates can handle. And the magnetic fields will pierce through the superconductor, and for one subset of superconductors, that's enough for it to completely lose superconductivity. Under those conditions. Take the magnet away and you keep it at its

critical temperature, it goes back to being a superconductor. But in the presence of powerful enough magnetic fields that can overpower the superconductive material and it just becomes a regular conductor again. Now, as I mentioned, there are magnets that can do that and will disrupt superconductors, but there are other types of superconductors they can actually kind of roll with the punches a little bit. So in this regard, there are two broad classifications that we can talk about

with superconductors. There's type one. This is the type that will lose superconductivity in the presence of a strong applied magnetic field. Then you have type two superconductors. These will actually continue to operate as a superconductor even in the presence of a strong applied magnetic field. It's just that at the points where the strong magnetic field intersects with

the superconductor, you get non superconducting material. So like within the same mass, just imagine you've got a big old puck of the superconductor material, and you've got this strong applied magnetic field that intersects with a superconductor material at that local point where there's that intersection, that would no longer be performing like a superconductor. But other areas of the puck that are not intersecting with this magnetic field continue to act like a superconnector. This is a type

to superconductor material. This is why we're able to use superconductors in labs that involve really powerful magnets. So, for example, the large hadron collider particle accelerators, they need really really strong magnets in order to drive those sub atomic particles at speeds that are close to the speed of light, but they also need superconductors. In order to do that, and if there were no type two superconductor material out there, it wouldn't work because the magnets would end up shutting

down the superconductors. They would just become regular conductors. You would lose too much energy in the form of heat, and the whole operation wouldn't work. So fortunately, there are these type two superconductors out there that can kind of localize where the disruption happens and the rest of the material can still perform as a superconductor. It's pretty mind blowing. Now, there are some big drawbacks with superconductors, as I have

describe them. I mean, you've got to super cool the stuff, which means making use of materials of like liquid nitrogen or liquid hydrogen, which is really expensive. It's dangerous. I mean, this material is so cold that it will cause incredible damage if you were to come into contact with it

for any you know, sufficient length of time. And it's really hard to use this stuff like it's it's got a huge barrier to being able to do it, which means that our applications for superconductors are by necessity really limited. They have to be limited to just the stuff that really needs the superconductors to work and are like huge like moonshot level experiments and scientific research stuff like particle accelerators, Like that's such a huge undertaking that using superconnectors as

part of the whole process. But you can't use superconductors to do more mundane stuff because it's way too expensive and complicated to make it practical. It just it doesn't work. Now, you can actually adjust that critical temperature I was talking about, You can actually make that higher so that you can operate at higher temperatures and still have super conductivity, But only if you're increasing the pressure that's on the system. So it has to be in a pressurized chamber. Right.

This is why like the hottest superconductor can operate at you know, minus twenty five degrees or whatever it might be. It's because it's inside a system that has incredible pressure applied to it. So again you're even as you remove the need to super cool it to like really really cold temperatures, you increase the need to have to create

these incredible pressure chambers. So it's a trade off, right, Like you're having to trade one difficult set of circumstances for another, and it still makes it very expensive and dangerous and complicated. Now, if we could make a superconductive material that performs as a superconductor, but does so at room temperature and at you know, ambient air pressure, that would change the world. When we come back, I'll explain how it would change the world and why some people

think we might already be there. Okay, we're back. I had mentioned that if we could make superconductive material that performs at room temperature ambient air pressure, it would really change everything. Well, it's pretty easy to imagine, right. Let's just take the really mundane example of that gaming pc I talked about earlier. Imagine you've got this crazy tricked out gaming pc. It's got the latest processors in it.

It's incredibly powerful, but all the circuits are made out of a material that's a superconductor, which means there's no heat being generated. It's not losing any electricity due to heat. This means a couple of really big things. One, we don't need any of those cooling systems anymore. There's no heat being generated, so there's no heat to take away. You don't need water cooling or even fans because you're not losing any energy due to heat. So a big

old chonker of a gaming PC would run silently. There'd be no moving parts. You would just have these incredible circuits made out of the superconductor material that can operate at room temperature. But also, we wouldn't need as much power to run our PC because none of our power is being lost in the form of heart. It's perfectly efficient. You would be able to achieve that level of performance with less power because you don't have to factor in

power loss at all. Perfect transmission of electricity would be a possibility, And that's interesting for a PC like you just suddenly think like, oh, I wouldn't need as big of a power supply, and I would mean a lower electricity bill. But let's expand that. Think about that for the purposes of actual electricity transmission from power plant to destination. What if all the power lines were made of the superconductive material. Now we would be able to transmit electricity

with no loss. You would have incredible efficiency. It would mean that we wouldn't need to produce as much electricity at least to meet our current demand. So if we were to assume that everyone was using exactly the same amount of electricity on the end of it as they are right now, then the amount of electricity we would need to produce would be much lower because we wouldn't lose anything in the process. We would end up having

a smaller demand on our power generation. That being said, between me and you, that's never how it works out. If our ability to produce electricity exceeds whatever the current demand is, we just typically see a demand rise in response. Right. It's not that, oh, now we're producing more electricity than we need. It's oh, now we can use more electricity, so now we need more. That's how it typically goes.

But it's still a nice thought, right, this idea of perfectly efficient transmitters, that would be amazing, And these efficient electrical systems would mean other stuff too, like batteries would last longer, right because again you don't lose any energy in the form of heat. More efficient systems means longer battery life even without an effective change to the batteries themselve levels. The improvement in the circuitry would be in

the batteries would last longer. They wouldn't be having to deplete so quickly, which means things like electric vehicles would see a boost and how far they could travel on a single charge. Again, not because the battery technology has improved, but because we're using the superconductive material for the circuitry within the electric vehicle. On the flip side, let's say it's in you know, consumer phones. Your phone would not

have to recharge nearly as frequently. You would be able to hold a charge much longer because again increased efficiency. It's actually really hard to express how big a deal this would be. I mean, it affects everything from environmental issues, to financial issues, to you know, all sorts of stuff. And I haven't even touched on what it would mean for science, like being able to have a room temperature operating superconductor and suddenly make things like particle accelerators orders

of magnitude easier to build. They would still be really complicated, Don't get me wrong. It's not like it would suddenly become something we could all make in our backyards. But it would be way easier than the systems that were needed to create the large Hadron collider, which means increasing accessibility to that kind of science, which means being able

to learn a lot more about our universe. Like these are the sort of big, big picture things that would be possible with an actual working room temperature superconductive material. But all of those possibilities depend upon a whole bunch

of stuff that we just aren't sure about yet. And the reason I'm talking about this at all, and you know I mentioned this in a news episode, but maybe you've heard about it otherwise, is that some researchers in South Korea reveal that a material they made in a lab, which they call LK ninety nine, appears to be super conductive at temperatures as warm as one hundred and twenty seven degrees celsius. That's two hundred and sixty nine degrees fahrenheit.

So that means that at any temperature below those, this material would be beneath its critical temperature and would operate as a superconductor. So two hundred and sixty nine degrees fahrenheit, y'all, it is hot outside, but it's not that hot. It would mean that we could make power lines out of this stuff, and if in fact it works as a superconductor, we could have a future with perfect transmission of electricity.

If so LK ninety nine consists of appetite lead and small amounts of copper, and the researchers from South Korea who developed this material actually laid out the process for baking it like they explained the process they did for creating this material. In turn, that has led to a ton of people, including some DIY scientists, to try and make this stuff for themselves and to test it out.

Now beyond the question of is this actually performing as a superconductor, which is an open question right it's as I record this, it has not been verified by experimentation, there are other questions that remain. So let's assume, just for the argument's sake, that yes, it does act as a superconductor for whatever reason, which is again just an example for this thought experiment. We would have other questions we would have to ask, like is it hard to synthesize?

Is it easy? Is it easy to create in the specific way so that it does perform as a superconductor? Or was that something of a happy accident that will be very hard to replicate if it is replicable, is it something that could be mass produced? If it could be mass produced, would it actually be suitable for things like power lines or is its composition such that it wouldn't really work in that it wouldn't be a good replacement.

What conditions will it act as a superconductor if it encounters a powerful magnetic field, is it like a type one superconductor material? And does it just stop performing as a superconductor until that magnetic field is removed. We need to know these answers now. There have been a couple of labs that have reported that, based on computer simulations

they have run, the material does appear to have superconductive properties. This, by the way, is not something that labs across the board have all agreed on, but some, including a couple of prominent ones, have said that they've run the simulations and at least on a simulation level, it seems to work out all right. But these are just simulations. They are not actual practical experiments with real material. It's all computers running numbers essentially. So skeptics are not satisfied just yet.

And I think that's a wise thing to be. I think it is wise to be skeptical. I think it could be optimistic, but keep some skepticism, or if you prefer, employ some critical thinking. I really want to believe these researchers have created a material that can work as a superconnector under room temperature conditions because of all the reasons

we've talked about and more. But we also have to remind ourselves that very earnest scientists thought they had done similar things in the past, only to later find out that's not actually what was going on. So we need to prepare ourselves for this potentially being another example of an interesting, exciting experiment that ultimately fails to measure up

to what was initially hoped. Maybe other labs will replicate LK ninety nine, maybe they will test it and see that it truly does perform as a superconductor under room temperatures and room air pressure. And if that's the case, we will have a truly technological revolution ahead of us. Even if we can't use it for everything, the things we can use it for it will be transformative. However, that has not yet happened as I record and published this episode, And maybe we find out that, in fact,

it's not a superconductor after all. Maybe there's some interesting things, Maybe there's some you know, regular magnetic material that's in there that's creating some interesting effects. We'll have to wait

and see. So my advice to you, as always is try to use critical thinking don't you know, you don't need to outright deny that it's a possibility unless there's like people who can show definitively that no, there's no way based upon our understanding of physics that this works, show that we have something fundamentally wrong with our understanding of physics, but that in turn would be truly huge.

But yeah, use critical thinking, but reserve some of that excitement just in case, as is possibly likely, it doesn't pan out. I hope it pans out. It would be truly incredible, and there are a lot of interesting debates going on in the scientific world about whether or not it's feasible, and I honestly don't know enough to be able to weigh in myself. I just want to be skeptical a little bit, but hopeful. That's kind of my approach. Speaking of hopeful, I hope you are all well, and

I'll talk to you again really soon. Tech Stuff is an iHeartRadio production. For more podcasts from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.