7. Superconductivity - University of Liverpool

If the electron is at the Fermi level E F , the velocity can be
obtained from:
Then the ion’s velocity is
E F = 1 2 mv2 e .
v 0 = F τ
M
where M is the mass of the ion.
The attraction only exists in the narrow region between
adjacent ions, and behind the passing electron. Also, it would
only last until the displaced ion returns to its rest position. The
time for this is the half of the period 2π/ω D . So a passing
electron with velocity v e leaves behind a trail of displaced ions
of length
l = v e × π
ω D
.
Superconductivity 59