5 ms·
You 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 co
by opwieurposiu 3y ago
You 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.
- inglor_cz 3y agoThe changes introduced by discovery of fire were very gradual. No Internet, no written language at all: any innovation back then could only spread as quickly as humans walked, and would temporarily stop at every significant geographic barrier such as sea. Compared to the discovery of fire, the changes from room temperature superconductors would be a flash fire.
- zamalek 3y agoI totally missed the impact of the internet, you are absolutely correct. Something else that I just noticed buried in the paper is that it can be readily deposited onto a substrate (search for UNIVAC in the paper, page 4). That's an incredibly big deal.
- louthy 3y agoFor the idiots in the room (me), could you explain why that’s a big deal? Does that make the material more robust and therefore usable in harsher environments?
- marcosdumay 3y agoCan you? The proposed model implies this relies on non-periodic impurities to achieve superconductivity, and the displayed strength is consistent with superconductivity only appearing on some places spread inside the material. This seems qualitatively different from YBCO. I don't know enough to be sure on the certainty of that model, but it seems well supported. So I'd be surprised if only improving the material quality was enough to make it strong.
- eru 3y agoYou are probably right about the details, but as a general observation: industrial products tend to get better over time as people learn how to make them more properly. The first batches coming out of a lab are usually terrible compared to what's coming out of factories a few decades down the line.
- jonititan 3y agoAre we talking the cool crystal selection spirals like RR et al use to make monocrystaline turbine blades? https://www.americanscientist.org/article/each-blade-a-single-crystal https://www.americanscientist.org/article/each-blade-a-singl...