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I have absolutely zero clue on materials science, chemistry or physics of this experiment. Can anyone explain to me why some teams are able to replicate it whil

I have absolutely zero clue on materials science, chemistry or physics of this experiment. Can anyone explain to me why some teams are able to replicate it while others can't?

7moritz7 3y ago
The Indian team didn't follow the actual instructions, they altered them thinking it yields the same substance but it appears the change in process did have an effect on it otherwise
- akhilkg 3y ago
  I think the Indian team's 2nd attempt (after also talking with one of the authors) followed the recipe as-is but was still unable to replicate it
danielheath 3y ago
Nobody is certain _why_ it works yet, and even the original team are only able to occasionally get it to work. The exact composition & impurities of the inputs are likely very significant.
euroderf 3y ago
> I have absolutely zero clue on materials science, chemistry or physics of this experiment. Same here. So I wonder, is a superconducting material actually useful "in production" if it is a material that (say) crumbles easily / is not at all flexible ? If we want superconducting wires, does the material have to be ductile ?
- ChrisRR 3y ago
  There's trade offs to everything. Just because it can't be extruded into wire doesn't mean it can't be cast for example. If it's not ductile it can maybe be supported by a more rigid structure. It totally depends on the application and how you work around the trade offs. Considering the alternative is supercooling helium and the dealing with the issues of containing such a small atom, managing the fragility of a room temperature superconductor may have huge beneficial trade offs
  - jacquesm 3y ago
    Usually flexibility is a function of how thin you can make something and what physical shape it has. You can shape it such that it becomes less flexible (think I beam for an example) or you can shape it so that it becomes more flexible (think foil). It's all the same material but the mechanical properties can be quite different. Practical use superconductor material is typically in a ribbon form, this allows for relatively easy shaping along one axis and still allows you to connect to it in a (relatively) simple way. An extra advantage of using a ribbon like conductor is that it allows for very close spacing without much loss in packing. Think 'oranges' versus 'boxes'.
- jacquesm 3y ago
  It needs to be flexible, but not so ductile that the magnetic fields produced deform it under the associated stresses, so preferably 'rigid' in one or two dimensions and flexible in the others. You then need to fixate it after you've made your assembly otherwise the stresses will rip it all to bits. This is why the copper wire in an electric motor is potted: the wire is what the forces in the motor act on, if the wire isn't rigidly fixed it will vibrate (and reduce efficiency) and that vibration will eventually wear through the insulation causing a short in the motor.
- cyberax 3y ago
  It can probably be made useful. Cuprate high-temperature (LN2, not room temperature) superconductors also have this problem, they are basically a brittle ceramic. However, it's now possible to make flexible tape out of them, by creating them as thin layers on a substrate. But it took three decades of experimentation to do that reliably.
ozgung 3y ago
Maybe it's like making an omelette. I have the recipe, I have the egg, yet I can't make it like a chef.
- distortionfield 3y ago
  Honestly I think this is very much the explanation behind why the team is standing behind their work. It’s so hard to replicate even just an omelette, I can’t imagine a material like this.
  - coolspot 3y ago
    Unless you’re slavic catgirl.
    - distortionfield 3y ago
      True, their twitter has been my most frequent check up on the situation
m3kw9 3y ago
The exact receipe wasn’t disclosed so there is some guess wirk
SkyPuncher 3y ago
The theory I've seen is there are two places that the copper can dope into the lead - one requiring higher energy. Likewise, the higher energy location is required for superconductivity. Right now, it seems to require a bit of luck to both (1) get that higher energy location to sit (2) getting a large enough grouping of it to be meaningful. It's kind of like playing Skee-ball at a fair. You aim for the center, but often miss into the outer rings. For this to work, you need to land a bunch of throws in the center in a row.

I have absolutely zero clue on materials science, chemistry or physics of this experiment. Can anyone explain to me why some teams are able to replicate it while others can't?

7moritz7 3y ago

The Indian team didn't follow the actual instructions, they altered them thinking it yields the same substance but it appears the change in process did have an effect on it otherwise

akhilkg 3y ago
I think the Indian team's 2nd attempt (after also talking with one of the authors) followed the recipe as-is but was still unable to replicate it

danielheath 3y ago

Nobody is certain _why_ it works yet, and even the original team are only able to occasionally get it to work. The exact composition & impurities of the inputs are likely very significant.

euroderf 3y ago

> I have absolutely zero clue on materials science, chemistry or physics of this experiment. Same here. So I wonder, is a superconducting material actually useful "in production" if it is a material that (say) crumbles easily / is not at all flexible ? If we want superconducting wires, does the material have to be ductile ?

ChrisRR 3y ago
There's trade offs to everything. Just because it can't be extruded into wire doesn't mean it can't be cast for example. If it's not ductile it can maybe be supported by a more rigid structure. It totally depends on the application and how you work around the trade offs. Considering the alternative is supercooling helium and the dealing with the issues of containing such a small atom, managing the fragility of a room temperature superconductor may have huge beneficial trade offs
- jacquesm 3y ago
  Usually flexibility is a function of how thin you can make something and what physical shape it has. You can shape it such that it becomes less flexible (think I beam for an example) or you can shape it so that it becomes more flexible (think foil). It's all the same material but the mechanical properties can be quite different. Practical use superconductor material is typically in a ribbon form, this allows for relatively easy shaping along one axis and still allows you to connect to it in a (relatively) simple way. An extra advantage of using a ribbon like conductor is that it allows for very close spacing without much loss in packing. Think 'oranges' versus 'boxes'.
jacquesm 3y ago
It needs to be flexible, but not so ductile that the magnetic fields produced deform it under the associated stresses, so preferably 'rigid' in one or two dimensions and flexible in the others. You then need to fixate it after you've made your assembly otherwise the stresses will rip it all to bits. This is why the copper wire in an electric motor is potted: the wire is what the forces in the motor act on, if the wire isn't rigidly fixed it will vibrate (and reduce efficiency) and that vibration will eventually wear through the insulation causing a short in the motor.
cyberax 3y ago
It can probably be made useful. Cuprate high-temperature (LN2, not room temperature) superconductors also have this problem, they are basically a brittle ceramic. However, it's now possible to make flexible tape out of them, by creating them as thin layers on a substrate. But it took three decades of experimentation to do that reliably.

ozgung 3y ago

Maybe it's like making an omelette. I have the recipe, I have the egg, yet I can't make it like a chef.

distortionfield 3y ago
Honestly I think this is very much the explanation behind why the team is standing behind their work. It’s so hard to replicate even just an omelette, I can’t imagine a material like this.
- coolspot 3y ago
  Unless you’re slavic catgirl.
  - distortionfield 3y ago
    True, their twitter has been my most frequent check up on the situation

m3kw9 3y ago

The exact receipe wasn’t disclosed so there is some guess wirk

SkyPuncher 3y ago

The theory I've seen is there are two places that the copper can dope into the lead - one requiring higher energy. Likewise, the higher energy location is required for superconductivity. Right now, it seems to require a bit of luck to both (1) get that higher energy location to sit (2) getting a large enough grouping of it to be meaningful. It's kind of like playing Skee-ball at a fair. You aim for the center, but often miss into the outer rings. For this to work, you need to land a bunch of throws in the center in a row.