Indeed, this will change pretty much everything if true. A true room temperature / ambient pressure superconductor will cause a revolution in so many fields that I find it hard to believe. But if... Let's wait for replication before throwing a party. This is on par with the discovery of the transistor and possibly bigger.
Superconductors have a current limit above which they are no longer superconductors. It is possible that a room temperature superconductor could be created that has a limit too low to be of any practical use.
It seems this is worth cautious excitement, but don't get too excited yet.
Oof, all right then. Perhaps there's room for improvement, but there would need to be a lot before this is useful/competitive even in lab settings.
For comparison, high temperature superconductors (in this context high temperature means tens of degrees kelvin) like the recently rather revolutionary ReBCO has critical current values measured in hundreds of thousands of amps per square centimeter. That would be a factor of a million.
It's a thin film according to the article linked, but there is no mention of how thin it is (it could be a monolayer) and there is no mention of how wide the film was so the 250 mA figure can not be used to determine whether or not there is 'room for improvement' or even a necessity for that (unless it was already normalized, for which I see no evidence). The 'Critical current' isn't mentioned at all in terms of the cross section of the conductor, just as a function of temperature and magnetic flux which they really should have provided to be able to make sense of the figure. ReBCO is 8 MA / cm^2 (that's million, not milli), the thin film layer they tested with could well be so thin that it is in the same ballpark or it could be a small fraction.
This is clearly a very early result and until they have more insight into how it works (assuming it really works...) we'll have to be patient before we get more meaningful figures on the actual current carrying capacity of thicker conductors made out of this stuff. They were happy enough to be able to prove superconductivity at room temperature and normal pressure, clearly they are still a ways away from being able to line up a comparison with ReBCO with respect to current density. But surely that will happen soon if this is real.
If it is a thin film it may have to be a thin film to get the effect in which case you still need a million of them bundled together to get comparable currents. It's not a certainty but a fact that dials back the excitement of this announcement from potentially world changing to interesting but quite limited applications.
>In 2008, Gozar et al. reported hightemperature interface superconductivity between metallic and insulating copper oxides(39). The
thinner the layer, the greater the stress-inducing effect, the greater the strain, which seems to be the higher the superconducting transition temperature. Therefore, we argue that the stress caused
by temperature and pressure brings a minute structural distortion and strain, which create an electronic state for superconductivity.
So the paper seems to confirm this, though the authors seem to be hopeful for general applications.
What we have here seems to be a clever trick to have ambient pressure superconductors by introducing crystal structure/microstructure stresses.
>But surely that will happen soon if this is real.
What I'm saying it that this is not so sure, may not be possible for a bulk material, may be insanely too expensive to be useful otherwise, and may be limited to very niche applications where milliamp superconductors might be useful (think sensors, microchips, and the like)
Sure is cool, but at the same time... cool your jets, eh?
Absolutely, but layers can be stacked (if they really are superconducting there won't be much of an issue to get rid of waste heat, there will be very little of that).
As for cooling my jets: I don't think we'll see any real application of this in the next 10 years at a minimum, this stuff is the first step on a very long road towards commercialization. From the first mention of the photo electric effect (~1890) to practical (1956), affordable (1990's) solar panels took roughly a century.
I hope that this superconductor, assuming it's real can be fast tracked given our much improved knowledge of materials and fabrication methods. But I'm realistic enough to realize how much work would still have to be done even if it is real. The road from the lab to the shelf is a long and expensive one and even in the best of scenarios I can't imagine anything on a timescale of less than a decade.
Let's wait to see what the maximum number of A/cm^2 is before determining if that is even necessary.
It's possible that they already normalized the figure, and if that's the case then 125 mA/cm^2 would be 'bad news' in the sense that even though the temperature and pressure are much better than other superconductors the critical current is much, much worse. But given the way the paper is formulated I'm not sure if that is a proper reading and it is very well possible that they are talking about a particular thin film sample (which would make it a small fraction of a square centimeter in cross section) and how much current they passed through that sample. In which case the situation would be much better already, especially if it turns out that the sample was extremely thin and/or narrow.
