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Phonons in cooper pairs (1 Viewer)

PhysicsMaths

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I i'm pretty sure that phonons aren't the region of positive charge; it's more to do with the electrostatic attraction of the positive crystal lattice.
Phonons are just packets of vibrational energy that is transferred from the leading electron -> crystal lattice -> trailing electron, enabling the electrons to overcome the electrostatic repulsion of like charges and form cooper pairs

Please correct me if I'm wrong
 

Kaido

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Yes, phonons are essentially vibrational energy in the crystal lattice. (You should mention this in the exam)
This next part may not be necessary (and is often just substituted with something like: "due to quantum phenomenon"):
So, when one of the electrons passes close to an ion in the crystal lattice, attraction between the negative electron and the positive ion occurs. This causes a vibration that passes from ion to ion in the crystal lattice until the other electron of the pair also absorbs the vibration. This means that the first electron of the Cooper pair has emitted a phonon and the second electron has absorbed that phonon
This next part IS necessary:
Through the continual exchange of phonons, the cooper pairs remain together and are able to travel through the lattice unimpeded
 

Mr_Kap

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Yeh we learnt that phonon are vibrational energy in the crystal lattice (which i remember because phone means sound and sound involves vibration of the medium...lol), and then cooper pairs form and remain through the continual swap of phonons between electrons.These cooper pairs allow the electrons to flow through the lattice unimpeded, leading to the zero resistance seen in superconductors.
 

sy37

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Yes, phonons are essentially vibrational energy in the crystal lattice. (You should mention this in the exam)
This next part may not be necessary (and is often just substituted with something like: "due to quantum phenomenon"):
So, when one of the electrons passes close to an ion in the crystal lattice, attraction between the negative electron and the positive ion occurs. This causes a vibration that passes from ion to ion in the crystal lattice until the other electron of the pair also absorbs the vibration. This means that the first electron of the Cooper pair has emitted a phonon and the second electron has absorbed that phonon
This next part IS necessary:
Through the continual exchange of phonons, the cooper pairs remain together and are able to travel through the lattice unimpeded
bit off topic but I chuckled when I read that because I've seen that phrasing alot, great post otherwise.
 

leehuan

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In our study of physics, we can technically call them 'virtual phonons' when referring to the BCS theory.

How this relates to charge is only because, if you consider the lattice it is full of positively charged metal ions. So when the lattice is distorted and the phonon causes two ions to attract in the lattice, you form a positive region. This is what the cooper pairs are related to.
 

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