Re: MPB solver for lossy media

On Thu, 4 Jan 2007, Ramamurthi, Badri N (GE, Research) wrote:
> I'm currently using MEEP for photonic crystal simulations and have
> lately wanted to explore the possibility of freequency domain methods
> such as MPB to try and see if I can speed up the computations. One of
> the arguments against using MPB that I've heard is that it cannot
> simulate lossy media, which is what I currently have. I wanted to verfy
> with you if this is true.

That's correct, Meep can only model lossless systems, at least directly. 
If you directly want to model include absorption loss, you need to switch 
to a different code, e.g. our FDTD code (Meep) supports absorption.

On the other hand, if you have dielectric materials where the absorption 
is small (Im epsilon << Re epsilon), then this is probably overkill.  In 
this case, it is very accurate to compute the modes of the lossless system 
and then to evaluate their losses via perturbation theory (a simple 
integral of the energy density in the absorbing media).

Steven