Understanding Electron Attraction in HTSC Superconductors

[uWave_Matt]

This has been discussed to death around here I imagine - Cooper pairs and whatnot - so I'll try to be specific and not ask too broad of a question here.

I did a little work with superconductors and I'm working on a passage for my thesis. I'm trying to provide background on Type I and Type II superconductors and I'm working on a general explanation of BCS theory and its limited application to Type II superconductors - I'll be talking to electrical engineers, not physicists.

The question is: Is it accurate to say that, in a Cooper pair, an electron is attracted to the position of its counterpart, rather than to its counterpart? It seems that the electron attracts surrounding oppositely charged atoms in the lattice of the HTSC causing the lattice to bend in towards the electron and create a slightly more concentrated charge increasing potential and attraction. The force on the coupled electron would pull it towards the new high-potential area overcoming repulsive forces between the two electrons due to the stronger attractive force from the lattice.

Am I on the right track here or do I need to head on over to the physics library and pick up a few more books?

 

[ZapperZ]

This has been discussed to death around here I imagine - Cooper pairs and whatnot - so I'll try to be specific and not ask too broad of a question here.

I did a little work with superconductors and I'm working on a passage for my thesis. I'm trying to provide background on Type I and Type II superconductors and I'm working on a general explanation of BCS theory and its limited application to Type II superconductors - I'll be talking to electrical engineers, not physicists.

The question is: Is it accurate to say that, in a Cooper pair, an electron is attracted to the position of its counterpart, rather than to its counterpart? It seems that the electron attracts surrounding oppositely charged atoms in the lattice of the HTSC causing the lattice to bend in towards the electron and create a slightly more concentrated charge increasing potential and attraction. The force on the coupled electron would pull it towards the new high-potential area overcoming repulsive forces between the two electrons due to the stronger attractive force from the lattice.

Am I on the right track here or do I need to head on over to the physics library and pick up a few more books?

This picture is fine if you intend to present a "cartoon" picture of the paring interaction.

BTW, why are you specifying that this is for HTSC (assuming that you are using HTSC to mean "high Tc superconductor"). What you are describing is thought to be valid for conventional superconductors. While the consensus is there for paring to occur in HTSC, the mechanism is still being debated. What you have described is paring due to phonons. This is still controversial in HTSC. I would not illustrate this cartoon picture by invoking that family of material.

Zz.

 

[nbo10]

I'm working on a general explanation of BCS theory and its limited application to Type II superconductors -

BCS theory applies to type II superconductors.

The question is: Is it accurate to say that, in a Cooper pair, an electron is attracted to the position of its counterpart, rather than to its counterpart? It seems that the electron attracts surrounding oppositely charged atoms in the lattice of the HTSC causing the lattice to bend in towards the electron and create a slightly more concentrated charge increasing potential and attraction. The force on the coupled electron would pull it towards the new high-potential area overcoming repulsive forces between the two electrons due to the stronger attractive force from the lattice.

Am I on the right track here or do I need to head on over to the physics library and pick up a few more books?[/QUOTE]

Head over to the library, maybe look up Tinkham. The pairing isn't performed in real space; i'ts performed in k space.

 

[uWave_Matt]

This picture is fine if you intend to present a "cartoon" picture of the paring interaction.

BTW, why are you specifying that this is for HTSC (assuming that you are using HTSC to mean "high Tc superconductor"). What you are describing is thought to be valid for conventional superconductors. While the consensus is there for paring to occur in HTSC, the mechanism is still being debated. What you have described is paring due to phonons. This is still controversial in HTSC. I would not illustrate this cartoon picture by invoking that family of material.

Zz.

I was aware that the theory describing the mechanism of conduction in type II superconductors is still being debated - for some reason I thought I read somewhere that this type of attraction still held true in type II (HTSC). That's alright. I'll probably be doing a brief description of type I (conventional) as well so I'll just illustrate this there.

Head over to the library, maybe look up Tinkham. The pairing isn't performed in real space; i'ts performed in k space.

Sounds like I need to get out my old Semiconductor Physics notes...thanks for the pointer.

 

[ZapperZ]

I was aware that the theory describing the mechanism of conduction in type II superconductors is still being debated - for some reason I thought I read somewhere that this type of attraction still held true in type II (HTSC). That's alright. I'll probably be doing a brief description of type I (conventional) as well so I'll just illustrate this there.

Where did you read this? There are type II conventional superconductors. The mechanism for these are described via the BCS theory.

All HTSC are type II superconductors, but not all type II superconductors are HTSC. You need to check your logic a bit here.

Zz.

 

[uWave_Matt]

Where did you read this? There are type II conventional superconductors. The mechanism for these are described via the BCS theory.

All HTSC are type II superconductors, but not all type II superconductors are HTSC. You need to check your logic a bit here.

Zz.

That's my mistake. I've just become so accustomed to associating Type II with HTSCs that I've absent-mindedly used the terms interchangeably - something I probably need to watch out for while I'm writing my thesis.