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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Recall that <strong>the</strong> Debye frequency ω D is <strong>the</strong> maximum vibrational<br />
frequency in a lattice. This happens when <strong>the</strong> ion spacing is<br />
equal to a half wavelength:<br />
Compare this with <strong>the</strong> picture <strong>of</strong> <strong>the</strong> ions attracted by a<br />
passing electron:<br />
In both cases, <strong>the</strong> electron cloud in between would be deformed<br />
in <strong>the</strong> same way. We can expect <strong>the</strong> same restoring forces on<br />
<strong>the</strong> ions, and <strong>the</strong>refore <strong>the</strong> same frequency.<br />
Superconductivity 8