Breaking superconducting state

[cragar]

When the B field gets too high it breaks the superconducting state. And then the B field can exist inside the conductor. When the field increases to point where it breaks the state is this because the cooper pairs flowing near the surface experience a force on their spin and then break them apart.
The force would break them apart because the spins are opposite on the electrons in the cooper pairs. If it breaks the cooper pairs at the surface does it just do this layer by layer until the state is broken? I am talking about an external B field acting on the superconductor.

 

[Greg Bernhardt]

I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?

 

[cragar]

I didn't think that my question was that difficult, I guess I can start looking at papers about superconductors relating to this topic.

 

[DrDu]

Spin polarization is certainly important although there are also orbital magnetic momenta involved.
I think this layer by layer mechanism is only effective in type 1 superconductors. In type 2 conductors, more and more field tubes form inside the superconductor.

 

[pmacias]

I can explain that the phenomenon of breaking the superconducting state when the magnetic field gets too high is known as the "critical field." This is the maximum magnetic field that a superconductor can withstand before it loses its superconductivity.

The reason for this is related to the behavior of Cooper pairs, which are pairs of electrons that are bound together in a superconductor. These pairs have opposite spins, which allows them to move through the material without resistance. However, when a strong magnetic field is applied, it can exert a force on these pairs, causing them to break apart. This breaks the superconducting state and allows the magnetic field to penetrate into the material.

The breaking of Cooper pairs near the surface of the material is the first step in breaking the superconducting state. This process can continue layer by layer until the critical field is reached and the entire material loses its superconductivity.

It is important to note that this phenomenon only occurs with an external magnetic field acting on the superconductor. In a zero or very low magnetic field, the Cooper pairs remain intact and the material remains in the superconducting state.

In summary, the breaking of the superconducting state when the magnetic field gets too high is due to the force exerted on Cooper pairs, causing them to break apart and allowing the magnetic field to penetrate the material.