Le 26 October 2006, Steven G. Johnson, à bout, prit son clavier pour taper sur son écran: > On Tue, 24 Oct 2006, Loïc Le Guyader wrote: > >But so far I didn't succed. I can't get any flux for epsilon = -5 while I > >can > >for the case of epsilon = 5 in which I'm not interrested. I only get some > >strange #.# ! > > Currently you need to turn epsilon-averaging off if you use negative > epsilons (this is a bug in Meep 0.10 which will be fixed in the next > version). That's causing the #.# numbers, which are NaNs caused by things > blowing up. > > Just do: (set! eps-averaging? false)
First, thanks for answering. But isn't this the first line of my ctl file I'm using, which was in attachement ? And even with it it doesn't work. But if I tried with (material metal), then I get some kind of correct result. What is epsilon in this case, and why it doesn't work with epsilon = -5 ? > > >Moreover, I don't understand why it isn't possible to simply define a > >function which return the permitivity, given the frequency ? It would > >permit to use raw ellipsometry data of plenty of material, without > >having to decompose them in term of polarixability, which is not a so > >easy process. > > Because this is a time-domain simulation. Any frequency dependence must > be converted into a set of auxiliary differential equations that are > integrated in time, and you can't do this with a bunch of frequency data > points from experiment (unfortunately). > > (It would be nice to write code to automatically fit experimental data to > a sum of harmonic resonances of whatever, but this is a bit tricky.) Damn, I will have to fit the data then. -- _______________________________________________ meep-discuss mailing list [email protected] http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
