Superconductor conductivity comparison

We look at the superconductor conductivity for niobium calculated with different methods. In the dirty limit, the Zimmermann and Mattis-Bardeen expression are almost indistinguishable. When including the scattering rate in the Zimmermann superconductor conductivity, the graphs deviates from the dirty case. From the comparison, we conclude that scattering has to be taken into account for high-frequency problems.

The code can be found in ./examples/superconductor_conductivity_comparison.py and can be run with

poetry run ./examples/superconductor_conductivity_comparison.py