Residual Resistivity and Defects

Shown here are measured curves of the low temperature resistivity of Na with different defect concentrations
The resistivity is constant for very small temperatures.
In the "bend" it shows T 5 characteristics.
For most of the temperature range it is proportional to T.
Defects clearly do increase the residual resistance (the upper two curves are for Na with defects, the lower one for rather perfect Na); the effect can be much large in other metals or for larger defect densities.
residual Resistivity

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go to 2.2.1 Conductors

go to Specific Resistivity as a Function of Temperature

© H. Föll (Advanced Materials B, part 1 - script)