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Comment by ninkendo | Hacker News Reader

I’m not an expert on this, but I think superconducting wires have an current limit, as a current flowing creates a magnetic field which the superconductor has to repel. I read that the paper states a very low current limit for LK-99, meaning it loses superconductivity once a very modest amount of current is passed through it.

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It's hard to tell what the critical current density of LK-99 is, because their sample is porous and probably very impure. They measured the critical current they could pass through a sample, but the conducting cross-section is somewhat unknown. Its high critical temperature suggests that it should probably have a higher current capacity than other superconductors. That said, in the extremes, current density is also limited by tensile strength, because electromagnetic coils repel themselves.

Is there any indication of what the breakdown voltage of LK-99 might be?

Couldn’t you bind it in resin?

That is.....kind of a huge limitation of the technology lol. Still very cool but less hype

I believe the implication is that LK-99 is basically a demonstration of an entire class of materials which should have room-temp superconduction properties. IE we can enumerate through the entire class and find the ones with the properties we want.

There is no reason to assume that even if it's real.

In fact, the tight tolerances of this seem to indicate the opposite.

At least according to this wikipedia chart on superconductor discovery timelines[1], it seems like most discoveries aren't one-off.

I have no knowledge in this area though.

[1] https://en.wikipedia.org/wiki/History_of_superconductivity#/...

A limitation...at ambient temperature and pressure.

Usually this is an optimization frontier, where something that has tetchy critical current/field at high temperature is going to have very good critical current/field at the same temperature as a lower-Tc superconductor.

If it superconducts at all at room temp, cooling it down even to 200K (about dry ice temp - quite cheap to do) could get you something very usable.

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