Isn't it a faux pas to put the degrees-symbol after the unit K?
Clearly K is an element of some kind of algebraic structure here
Ah yes, K, the Potassium Constant
Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
61–70 of 389 posts
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#62Earlier quoted context omitted.
MRI machines work using superconducting magnets as does the LHC. So you better believe it buddy.
Why do MRIs need zero resistance vs incredibly low resistance?
The more you crank up the field and gradients the better resolution you can get. Being able to take MRI of a beating heart depends on that sort of thing.
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#63Looking at the key temperature-resistivity graphs, this feels like the data doesn't support the conclusion that there's a superconductor here. The temperature-resistivity graphs of superconductors I've seen all have a fairly steep cutoff--a sharp, vertical line at critical temperature. The log-scale here complicates my intuition, but what I see is a gradual transition into noise range. Also, the graphs I've seen have…
Not a superconductor expert, but resistance exponentially decreasing with temperature is not a normal phenomenon in most cases!
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#64Earlier quoted context omitted.
Is this kind of thing typical for experiments working to confirm such significant results, or is there a mad rush to publish? Do you really get a lot of prestige from confirming somebody else's result? I would have thought the risk to reputation from sloppy work would far outweigh it (see: the cold fusion shenanigans).
Probably a lab that confirms any piece of it will get a significant share of attention and acclaim. I heard the research group got scooped by a former researcher. Former researcher outed them before they were ready for all the relevant questions. Not a particularly good thing to do for a career to out colleagues like that.
> Probably a lab that confirms any piece of it will get a significant share of attention and acclaim.
Why is that though? They're taking a discovery that somebody else came up with, and (mostly) follow a recipe they're given.
I mean if they were synthesizing a theorized substance or significantly improving its production, or measuring an effect that was previously undetectable by known instruments and experiments then those things would deserve acclaim on their own.
Not saying they aren't good scientists and labs working on this or reproducing is worthless, the reward just doesn't seem big enough not to be meticulous about it. If you're right then you'll be one of the dozens of labs that reproduced it and all credit goes to original discoverers. If you're wrong you'll be the ones who bungled the experiment and share just about equal blame.
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#65Earlier quoted context omitted.
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.
Especially if the material happens to have photo electric properties too...
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#66Question for the cognoscenti: supposing that LK-99 superconducts with T_c = 110 K, how significant a discovery would this be? I.e., does it establish a brand new class of high-T superconductors, or is it merely one unremarkable member of a known class? Further, does it offer advantages over other high-T superconductors such as ease of fabrication or cost?
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#67Earlier quoted context omitted.
Probably a lab that confirms any piece of it will get a significant share of attention and acclaim. I heard the research group got scooped by a former researcher. Former researcher outed them before they were ready for all the relevant questions. Not a particularly good thing to do for a career to out colleagues like that.
> Probably a lab that confirms any piece of it will get a significant share of attention and acclaim. Why is that though? They're taking a discovery that somebody else came up with, and (mostly) follow a recipe they're given. I mean if they were synthesizing a theorized substance or significantly improving its production, or measuring an effect that was previously undetectable by known instruments and experiments the…
In science the fights are so fierce because the stakes are so small...
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#68I don’t understand the physics, but it feels like a truly zero resistance conductor would violate some law of thermodynamics or something. Is a superconductor truly zero impedence or just very very very low? Because I’m seeing a lot of these graphs with something like: “0.00001ohm” as the y-axis floor.
Not an answer, but if you think superconductor is weird, look up superfluid, now that's going to make your head spin.
Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#69Earlier quoted context omitted.
Zero loss diodes seem pretty useful.
I don’t think this would be zero-loss diodes - it would probably superconduct in some x-axis while being non-superconducting in the y- and z-axis. Even then, it’s not clear to me what the conductivity is like in the non-superconducting axies.
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Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O
#70Looking at the key temperature-resistivity graphs, this feels like the data doesn't support the conclusion that there's a superconductor here. The temperature-resistivity graphs of superconductors I've seen all have a fairly steep cutoff--a sharp, vertical line at critical temperature. The log-scale here complicates my intuition, but what I see is a gradual transition into noise range. Also, the graphs I've seen have…
Not a superconductor expert, but resistance exponentially decreasing with temperature is not a normal phenomenon in most cases!
Most semiconductors have a thermal regime where that happens, it's just a relatively small regime, I thought?