[postmortembees]

Yeah, it seems like (to me, a naive layperson) to be similar to how a prince rupert's drop exerts strong forces thanks to the mechanism of its cooling/shape. The copper somehow forcing other structures to form in an atypical way which enables the superconductivity.

And even at 250mA, there'd be tons of different usecases for a superconductor.

[barelyauser]

It is not limited to 250mA overall. A physically larger specimen would be capable of more current.

[danbruc]

I got this wrong, they also produced a thin film in addition to bulk material. And my worry was that one could maybe not easily scale this up in case the effect relied on it being a thin film in which case you can only make ever so wide before it becomes impractical or you have to layer or fold the thin film which might also be problematic. But as I said, I just read this wrong.