Question
Electrical conductivity. Derive an approximate expression for the electrical conductivity, $\sigma$, of a degenerate electron gas of density $n$ electrons $/ \mathrm{cm}^3$ in terms of an effective collision time, $\tau$, between the electrons.
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The electrical conductivity can be expressed in terms of the current density \(J\) and the electric field \(E\) as follows: \[ \sigma = \frac{J}{E} \] Show more…
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