Help with the BCS theory of Superconductivity please (1 Viewer)

[J-Wang]

Ok, so I know that with the BCS theory of superconductivity, the temperature must be below the critical temperature to allow for the formation of Cooper pairs. These low temps are required for the repulsive forces of the electrons to be overcome, attracting each other to form Cooper pairs and also so that the phonons are prevented. These Cooper pairs are then able to pass through the lattice unimpeded, interacting with phonons within the lattice which propel them along to conduct.

My question is if the Cooper pairs pass through unimpeded, how do they interact with the phonons? Also, is there anything about the BCS theory which I need to know in more detail?

 

[someth1ng]

The first electron movies into the lattice, the metal ions are positive and the electron is negative making them attract. As there are more positive ions, it makes a region of net positive charge which attracts a second electron. It is said that the first electron emits a phonon and the second electron absorbs a phonon - these two electrons which transfer phonons are called a "Cooper pair" and have a weak bond.

Above the critical temperature, the lattice vibrates with more energy than the binding energy of Cooper pairs causing them to be scattered and so, Cooper pairs cannot form and hence, electrons cannot move through the lattice unimpeded.

That should be the least that you know.