Alternative materials in high temperature superconductors

[hamiiiii]

TL;DR Summary

Why don't researchers look into using alternative materials in superconductors?

I don't know much about the theory behind superconductivity and how exactly material scientists are able to create new materials so if this is a stupid question I do apologize in advance. While looking though a list of high temperature conductors I noticed that cuprates are composed of oxygen (2nd most electronegative element) and copper (2nd most conductive). My question was would superconductors formed of Ag and F have higher critical temperatures? What about Tin (as 2 dimensionally tin has higher conductivity than silver) and Fluorine? Or Graphine and Flourine? Have scientists already thought of using these materials and have they tried them out? Or is there no correlation between the electronegativity of oxygen and the conductivity of copper in superconductivity?

 

[Lord Jestocost]

TL;DR Summary: Why don't researchers look into using alternative materials in superconductors?

They do. See, for example, the report “Materials Design for New Superconductors“ by M. R. Norman (Rep. Prog. Phys. 79 074502).
(https://arxiv.org/abs/1601.00709)

 

[Vanadium 50]

stupid

Not the word I would use, but "I don't know anything about superconducting materials but I am sure all the people who do are doing it wrong" is a tough position to hold.

As @Lord Jestocost said, people are looking at all sorts of materials. When "Why don't they?" has the answer "but they do" it is also a tough position to hold.

You can't just pick one property, and you can't infer compound properties from elements. Magnesium doesn't superconduct and boron is an insulator, but magnesium diboride is a superconductor. Other properties that matter are oxidation state, crystal structure, atomic size, and so forth.

 

[hamiiiii]

They do. See, for example, the report “Materials Design for New Superconductors“ by M. R. Norman (Rep. Prog. Phys. 79 074502).
(https://arxiv.org/abs/1601.00709)

Ok I did not know that thank you that is intresting reading.

 

[hamiiiii]

Not the word I would use, but "I don't know anything about superconducting materials but I am sure all the people who do are doing it wrong" is a tough position to hold.

As @Lord Jestocost said, people are looking at all sorts of materials. When "Why don't they?" has the answer "but they do" it is also a tough position to hold.

You can't just pick one property, and you can't infer compound properties from elements. Magnesium doesn't superconduct and boron is an insulator, but magnesium diboride is a superconductor. Other properties that matter are oxidation state, crystal structure, atomic size, and so forth.

I wasn't trying to infer that, I was just wondering why the highest temperature superconductors known are composed of the elements with the 2nd highest electronegativity and conductivity, and if that could be related. I honestly don't know much about materials science so I was wondering if it is just a coincidence or if the two are related.

I was curious if anyone has tried to make a high temperature superconductor using materials which are more electronegative and conductive to see if they had any promising results, because if they did then that might prove that those properties are kind of related. Flourine, Silver, and Tin apparently are more conductive 2 dimensionally than copper so I would be interested to see what happened if anyone tried those.

The conjecture was that they would use the exact same structure of the cuprates, but every O atom would be replaced with a F atom and every Cu atom would be replaced with Ag or Sn. Apparently someone did do a study and simulations show that Ag-F could have a higher critical temperature (https://en.uw.edu.pl/superconductivity-at-record-high-temperature/).

I did not intend to imply that research is using the wrong method, I am just curious to see if anyone has tried these materials and what the research method is.

 

[Vanadium 50]

Silver halides are ionic compounds, and therefore insulators. They will not superconduct.

 

[hamiiiii]

Oh. So the article was misleading?

 

[Vanadium 50]

Oh. So the article was misleading?

You can answer it:

1. Did they sytnhesize any of this material?
2. Does it superconduct?
3. How many years have they had to follow up on the first two?

 

[pines-demon]

Historically it is possible that we find good superconductors in unexpected materials. In the 60s the promising Matthias rules indicated very successfully what made a good superconductor, however all the rules have been broken since. Theory does not help much either, BCS theory does not explain high-temperature superconductors and we still do not have its replacement. Who knows maybe tomorrow we find room temperature superconductivity in dish soap.

 

[hamiiiii]

Historically it is possible that we find good superconductors in unexpected materials. In the 60s the promising Matthias rules indicated very successfully what made a good superconductor, however all the rules have been broken since. Theory does not help much either, BCS theory does not explain high-temperature superconductors and we still do not have its replacement. Who knows maybe tomorrow we find room temperature superconductivity in dish soap.

So the research method for discovering new high temp superconductors is more of a guesstimate type of approach, as we lack a definitive theory on how they work?

 

[berkeman]

I don't know much about the theory behind superconductivity and how exactly material scientists are able to create new materials

Thread prefix changed A-->I.

 

[pines-demon]

So the research method for discovering new high temp superconductors is more of a guesstimate type of approach, as we lack a definitive theory on how they work?

(not an expert) yeah I mean it is kind of well known that the theory of high-temperature superconductivity is a big open problem. There have been recent advances though, J. C. Séamus Davis has recently won some prizes for finding new hints of what mades cuprates superconductors. There have been proposals to use AI or quantum computing to notice more patterns and search (what we think is) the possibility space in a better way.

Maybe you know about the last year story of LK99, clearly a fake superconductor and a worse-than-undergraduate paper, but many people in the superconductivity community took the job of verification seriously because there was no way using theory to be certain if it was superconductor or not.

 

[hamiiiii]

Yeah I heard that there is a possible explanation for high temperature superconductors called superexchange, I couldn’t really find anything explaining it in a down to earth manner. I did see a lot of articles written on it, but most of the explanations were not very specific on if it is a confirmed theory, I’m guessing it isn’t .

 

[DrDu]

Hamiiiii (I hope, I got the correct number of "i"s!), you have a good chemical intuition. In fact, Silverhalides have been studied for exactly these reasons as potential superconductors. See for example the article by the Nobel prize winner R. Hoffmann:
https://onlinelibrary.wiley.com/doi...orpnfp_T2h85zt6LFw8mjl-aI_MFa3lfG1Jw5w1hDgfLA
Searching for Silver fluoride superconductor in Google scholar yields tons of articles on the subject.