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Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

arxiv.org

31–40 of 389 posts

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#31

A 110k superconductor would not be revolutionary since we already have some in that vicinity.

An entirely new category of superconductor could well be revolutionary even at this temperature, for several reasons. It could be the first one of a family with variants that go up to room temperature. It could be cheaper to produce or have other desirable properties for commercial applications. And it could lead to advances in theory that would allow prediction of other unknown superconductors.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#33

Summary of events so far: The claim: Room temp (~300K) superconductor exists and we got it! The replication attempts: The production method is so poorly documented only a fraction of the samples being made shows any interesting properties. And among those interesting ones, results varies. Very few, if any, attempt actually completely shows the entire spectrum of properties and behaviors of a true superconductor at ro…

Some literature suggests its a "one dimensiononal" superconductor only kinda works in tiny monocrystaline grains.

...But maybe thats even more interesting for, say, microelectronics? Especially if the resistance orthogonal to the superconductivity is high, if such a thing is even possible?

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#34
post #26

> In conclusion, we successfully synthesized the compound Pb10-xCux(PO4)6O, and observed the zero resistance above 100 K. However, the Meissner effect has not been observed yet in our samples, which suggests that the superconducting volume is relatively low. In conclusion, ... nothing?

It's definitely something, rather big something, to observe zero resistance above 100k

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#35

Summary of events so far: The claim: Room temp (~300K) superconductor exists and we got it! The replication attempts: The production method is so poorly documented only a fraction of the samples being made shows any interesting properties. And among those interesting ones, results varies. Very few, if any, attempt actually completely shows the entire spectrum of properties and behaviors of a true superconductor at ro…

Some literature suggests its a "one dimensiononal" superconductor only kinda works in tiny monocrystaline grains. ...But maybe thats even more interesting for, say, microelectronics? Especially if the resistance orthogonal to the superconductivity is high, if such a thing is even possible?

Zero loss diodes seem pretty useful.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#36

I'm very much conservative about this paper because while the graph in Fig. 3a says $T_c^{zero}$ being 110 K, the "zero" resistance is actually only 1e-5 Ω (!) and even if the sample is possibly superconducting its critical temperature would be much lower than 110 K anyway. I'm aware of the difficulty in obtaining larger samples, but the label in that graph is really misleading regardless.

Well, it's at a 1mA test current (I'm assuming a 4 point probe to mitigate contact resistance) so 10u Ohm would give a 10nV DC signal. That's a pretty small voltage signal and comparable to a fairly standard chopper stabilized instrumentation amp rms noise at room temp near DC.

I'm not sure whether higher currents are all that reasonable. Cooling the precision amp is an option to reduce the noise figure, but at that point you'll want optical isolation and battery supply too.

https://www.analog.com/media/en/training-seminars/tutorials/...

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#37

A 110k superconductor would not be revolutionary since we already have some in that vicinity.

This is not about 110K, this is about trying to verify the results related to LK-99.

The LK-99 that is room temp superconductive seems quite difficult to produce at this early stage. But these researchers were able to produce their not-as-good version of LK-99 and at least verify very close to superconductivity at 110K. This makes the LK-99 room temp superconductivity claims that much more plausible.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#39

A 110k superconductor would not be revolutionary since we already have some in that vicinity.

That's what I'm not understanding about this frenzy. Seems like this already kind of exists?

The original report is billed as a "room temperature superconductor" (iirc up to 28c). If it is indeed a superconductor at room temperature, it would be the first of it's kind and enable functional usages for superconductors previously impossible.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#40

A 110k superconductor would not be revolutionary since we already have some in that vicinity.

First, at a minimum it validates that the researchers found a novel rare superconductor at ambient pressure, and are not frauds.

Second, the new mechanism of superconductivity may lead scientists to explore other materials with similar properties that may work better.

Third, the synthesis may not be completely spot on yet. It has been just 4 days of attempting replication, and this result is pretty good in that context.

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