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A room-temperature superconductor? New developments

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721–730 of 821 posts

Re: A room-temperature superconductor? New developments

#721
post #714

Earlier quoted context omitted.

Don't forget: Soap/handwashing, antibiotics, the smallpox vaccine, the Haber-Bosch process, blood transfusion, anesthetic and PCR!

soap is a good one for sure; the others might turn out to be less important than the transistor time will tell

Haber-Bosch is the reason there are over 7 billion humans on Earth instead of closer to 2 billion. It's very difficult for any digital technology to compete with that.

Re: A room-temperature superconductor? New developments

#722

Earlier quoted context omitted.

A room temperature and pressure semiconductor is more an astoundingly large jump forward in the space than something that defies known physics.

That doesn’t track. The EmDrive was legitimately pushing a premise that we had some fundamental law of physics wrong. Superconductors are pretty well understood, they’ve been around for a while. Finding a room temperature one isn’t that big of a jump, it’s just a really hard one to make.

Perhaps it would have been clearer to say "than it is something..." . Too late to edit at this point unfortunately.

Re: A room-temperature superconductor? New developments

#723
post #569
post #516

Earlier quoted context omitted.

None of the things you listed are limited by the conductors in them. The efficiency of high voltage AC power lines is limited by capacitive coupling to ground. Battery charging is limited by the cell chemistry. CPU heat output is limited by the resistance of the semiconductors. Turns out metals (in particular copper) are already incredibly good conductors.

In the RF world (particularly at mm-wave frequencies), even copper has very non-negligible losses. In most passive circuits conductor loss is the limiting factor of performance. No idea if this material retains the same properties at such frequencies, and is compatible with typical lithography or other fabrication techniques, but it'd be amazing if so.

Particle accelerators sometimes use superconducting niobium resonators at e.g. 1.8K offering a Q of 5e10 at 1.3 GHz. But apparently their surface resistance scales with the square of frequency, unlike the square root in normal copper.

So maybe just just t normal conductors like copper, silver, graphene (assuming the latter can be commercially made to surpass silver in RF surface resistance).

Re: A room-temperature superconductor? New developments

#724
post #516

Earlier quoted context omitted.

None of the things you listed are limited by the conductors in them. The efficiency of high voltage AC power lines is limited by capacitive coupling to ground. Battery charging is limited by the cell chemistry. CPU heat output is limited by the resistance of the semiconductors. Turns out metals (in particular copper) are already incredibly good conductors.

> CPU heat output is limited by the resistance of the semiconductors. This is not true anymore. At leading edge process nodes (i.e., smaller conductor pitch), the bulk resistivity of copper changes dramatically because it is increasingly dominated by ballistic electron scattering on the interfaces and grain boundaries: surface area has decreased as a fraction of volume and the average grain size has shrunk to fit ins…

No it pretty much is true, well it's the power draw from switching transistors and from leakage losses.

Resistance in the metal wires is not so much a problem for power as it is for signal propagation delay. That is the biggest problem with R skyrocketing in M0/1.

And backside power delivery is to relieve congestion in the interconnects. That's typically one of the limiting factors in complex logic designs now, transistor densities of under 70% aren't uncommon.

That's what "Removing the power signal and signal line to just a signal line would free up space for more transistors." line is about in the link. Power delivery losses aren't nothing, but they aren't a big fraction of energy in today's CPUs.

Eliminating most wire delay would be a huge benefit though, and could be a pretty big revolution. Not just within the core or on the die. You're still going to have to switch those transistors and burn current on leakage though, so no cold CPUs just yet.

Re: A room-temperature superconductor? New developments

#725
post #716

Earlier quoted context omitted.

I don't understand how your comment implies a lack of subsidy, it only states that the people harvesting the material can make money off of it. Which would be true if it was subsidized, too.

it's not such a politically popular activity as to attract subsidies; it is tolerated and pitied rather than lauded and promoted

No one is saying they are subsidizing people scavenging. They're talking about farther up the chain.

Re: A room-temperature superconductor? New developments

#726
post #612

Earlier quoted context omitted.

Superconducting powerlines would be able to transport DC electricity with 0% losses. To put this in context: you could put solar panels in California, and send every watt of power to Alaska or New York, while losing nothing in the transport.

Yeah at those kinds of scales I get doubtful. At those scales the electrical fields themselves begin to exert inertia on things, to the point that you could cut most power lines and they wouldn't stop catastrophically, they'd continue catastrophically (a problem that only gets worse with superconductors, as happened to CERN when they accidentally vaporised a length of superconductor that had become conductive ). It c…

Could you spot me a link to that CERN incident or on the topic of superconductors becoming conductive (looooool)? All I got for CERN was reports about gas leaks but I find myself very curious about the way superconductors fail now

Re: A room-temperature superconductor? New developments

#727
post #497

Earlier quoted context omitted.

> Can I have my flying car now? Let's not forget the flying skateboard of the film "Back to the future". I loved it in the film and it's a dream that I still have today - I'm now almost 50 years old so I would probably crash and get killed by using it, but I would still give it a try :)

Unfortunately, while you can indeed build hoverboards with superconductors and they do work, you still need a magnetic surface for it to ride over. I don't believe generalized hoverboards that will work on all surfaces like BttF are possible.

Wouldn't a hoverboard with rockets on the bottom and back work? I'm not saying it's feasible, just that it's utilizing the same basic science as jets and space travel.

Re: A room-temperature superconductor? New developments

#728

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

> Can I have my flying car now? Let's not forget the flying skateboard of the film "Back to the future". I loved it in the film and it's a dream that I still have today - I'm now almost 50 years old so I would probably crash and get killed by using it, but I would still give it a try :)

I mean, yeah, you'd need a very generous marketing budget to make a skatepark full of magnets so we can have hoverboards. Like the one Lexus already built: https://www.theverge.com/tldr/2015/6/25/8846785/lexus-hoverb...

Re: A room-temperature superconductor? New developments

#729

Earlier quoted context omitted.

Additionally you need to have the current to deliver in the first place. Having a grid that can dump 25-100 kwh into any given car in a couple of minutes is no small task if everyone is doing it.

The utilization factor would obviously be much lower than it would be if everybody charges at a lower rate so if the total amount of energy is equal that just means that individual vehicles will spend less time charging, and the grid will see - roughly - identical utilization on average but the peaks may be higher.

Probably worth pointing out that the peaks and troughs are what are challenging to deal with. Generators aren't generally great at changing output super fast.

I keep hearing battery tech is getting good, and the research I've seen suggests that more storage on the grid would improve efficiency by a lot, so I don't know if it would even pose a particular challenge if that sort of demand arose.. but overall utilization isn't really the limiting reagent.

Re: A room-temperature superconductor? New developments

#730

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

What things are we going to do with this material in the next 5 years? What things that I buy and use will be made better?

You know those joke buzzer/shocker rings? Well, they're going to get really, really good.
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