On Thu, 17 Jan 2008, Manoj Rajagopalan wrote: > I was thinking about why MEEP should allow only a real dielectric > constant. In the monochromatic case it would make sense to evaluate the > dielectric function at the frequency-of-interest \omega_0 and plug that > into Maxwell's equations, simplify, and solve but in the most general > case, a complex value would be required.
There is no computational problem with supporting a non-dispersive complex dielectric constant, or alternatively a frequency-independent conductivity (which would give an imaginary part of epsilon that varies as 1/omega). Although these materials are not physical, they are causal, and are useful for calculations involving a limited bandwidth. Complex dielectric tensors are also useful for gyrotropic (magneto-optic) media. We have some internal modified versions of Meep that support this. However, merging these modifications into an official Meep hasn't happened yet, partially because I have another student who has been rewriting the PML and timestepping code (largely to improve the PML effectiveness), and the two changes need to be merged. Regards, Steven G. Johnson _______________________________________________ meep-discuss mailing list [email protected] http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
