Documentation about materials question

[kitchenknif]

The documentation for how meep handles dispersive materials includes a formula for Drude-Lorentz dispersion, that is significantly different from models I've seen in FDTD-related literature.

Equation from your documentation:

Equation from, e.g., doi:10.1016/j.cplett.2007.08.027

For the model used and data from dot:10.1364/AO.37.005271, these two models would be equivalent, because conductivity is set to zero. But for fits where the conductivity is not zero, these two models are vastly different.

Am I misunderstanding something here?

[stevengj]

They are inequivalent when you have both σ and Lorentzians, but since both of them have to be fit to experimental data and both have the same asymptotic behaviors it doesn't seem like a problem.

You do have to do a separate fit, though, if you have a fit from the other form.