The Nature of the Cooper Pair - University of Liverpool
The Nature of the Cooper Pair - University of Liverpool
The Nature of the Cooper Pair - University of Liverpool
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We shall approximately represent <strong>the</strong> attractive potential as a<br />
function that is constant within <strong>the</strong> range l:<br />
where<br />
V (r) =<br />
�<br />
V0 =<br />
−V0 for r < l<br />
0 for r > l<br />
e2<br />
4πɛ0d 2δ.<br />
We have seen that <strong>the</strong> potential only exists within a narrow<br />
tube, so it is not exactly a spherical potential.<br />
However, if two electrons happen to be travelling in opposite<br />
directions and pass very close to each o<strong>the</strong>r, <strong>the</strong>n <strong>the</strong> potential<br />
has <strong>the</strong> same effect as a spherical potential, because <strong>the</strong><br />
electrons do not experience <strong>the</strong> potential outside <strong>of</strong> <strong>the</strong> tube.<br />
Superconductivity 12