[HN Gopher] Nickel superconductor works above -233degC threshold...
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Nickel superconductor works above -233degC threshold at normal
pressure
Author : PaulHoule
Score : 81 points
Date : 2025-03-09 17:43 UTC (4 hours ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| p1mrx wrote:
| Wikipedia shows 10 known superconductors at 40 K and ambient
| pressure. What's notable is that this is the first one to contain
| nickel:
|
| https://en.wikipedia.org/wiki/List_of_superconductors -- sort by
| Tc (K)
| littlestymaar wrote:
| Can you tell us more about why it is an interesting property?
| p1mrx wrote:
| If we're trying to understand how superconductors work, then
| it's useful to have more examples.
| mort96 wrote:
| Yes that makes sense, but why is Nickel specifically
| interesting?
| creddit wrote:
| Because it may lead to new classes of high temperature
| ambient pressure superconductors. Maybe even leading to
| room temperature + pressure superconductors.
| msandford wrote:
| Nickel itself isn't interesting. Any new material is
| interesting. Yet another YbCo-whatever wouldn't tell you
| as much as an entirely new metal. It would be just as
| interesting if it was titanium or vanadium or lithium or
| any other metal that hasn't ever been found in a
| superconductor before.
| hinkley wrote:
| From the article:
|
| > The -233degC threshold (40 K), often associated with the
| McMillan limit, marks a boundary beyond which conventional
| superconductivity theories become less predictive.
|
| So it's like finding a gas giant exoplanet that's in the
| "wrong" place. We understand Jupiter and Saturn. We don't
| understand a gas giant orbiting its star in ten days. Thats
| weird. And science can't progress when there is nothing
| "weird". It means all the data matches our models. It's
| boring. It has nothing to teach.
|
| A ten day orbit or a normal metal group superconductor are
| outside our comfort zone and may mean new physics.
| light_hue_1 wrote:
| Nature has a much better news article than phys.org:
| https://www.nature.com/articles/d41586-025-00450-3
|
| We have two classes now, copper and iron based
| superconductors that work at room temperature above 40K or
| so. Below 40K, there are countless superconductors and the
| mechanism they use breaks down at around 40K. There's no
| reason to think that a material which is a superconductor
| below 40K will have some variant that is one above 40K.
|
| Once we have evidence of superconductivity above 40K or so
| (at normal pressures) things change. Those materials follow
| different rules that we only partially understand. And there
| is reason to hope that variants exist which will be
| superconductors at even higher temperatures. There's no set
| barrier or upper limit once you cross the 40K threshold. One
| may exist, but we don't know it.
|
| What happened with copper, and iron (to a much lesser
| extent), is that we marched up the curve and eventually made
| superconductors with many real-world. Once you reach 77K
| (-195C) we're in business. The hope is that maybe we can do
| the same with nickel. This has traditionally only really
| worked well with copper-based compounds.
|
| Having a 3rd class of materials gives us a lot more options.
| And the more examples we have, the more likely we are to come
| up with some useful theory.
| ars wrote:
| If you are wondering why this matters: It's not for a commercial
| product, it's to help understand why some materials superconduct.
| boothby wrote:
| Hot* take: -233 is too cold for Celsius. I'm okay with folks
| reporting critical temperatures in C once they get near room
| temperature, but this is only 40K (which _is_ blazingly hot in my
| world, but regardless).
|
| But, it's cool to see the boundaries pushed on the McMillan
| limit, and that figure with a lazy Susan of sputtering targets
| looks fun.
|
| * pun acknowledged
| loufe wrote:
| I'm curious by what measure you suggest it's "too cold". Kelvin
| is an offset celsuis, so it's not like we're talking about an
| innapropriate order (like 10 000 000 grams vs. 10 tonnes).
|
| I would understand if it detracted from one's understanding,
| but I think this format is more accessible than assuming
| everyone knows what kelvin are, and it's explained in the first
| sentence. This is journalism, accessibility to science should
| be lauded while maintaining brevity for , IMO.
| hexaga wrote:
| Frame of reference. Kelvin immediately tells you the distance
| from absolute zero, which is at least somewhat relevant in
| this context. Celsius tells you the distance from liquid
| water which isn't very helpful in understanding the figure.
|
| I think fewer people know the offset between K and C than the
| fact that 0K represents absolute zero.
| rzzzt wrote:
| -196 is another point of reference that might be familiar
| to people interested in, ehm, cold.
| jayyhu wrote:
| For the layman, 0 degrees celsius is also a good proxy for
| the distance to "room temperature" superconductor.
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