Dear Liu, I suppose you can consider the nonlinearity as a some addition intermediate step in FDTD algorithm. So the amplitude of signal does'n affect the epsilon tensor (or epsilon value), just when we compute D field from E field (maybe vice-versa, E from D, I don't know exactly), we use something like this D := n_0 + n_2 * E^2... n_0 doesn't change! (n_0)^2 creates after output-epsilon...
You can See details for meep realization, e.g. here http://ab-initio.mit.edu/wiki/index.php/Units_and_nonlinearity_in_Meep BR, Alexandr _______________________________________________ meep-discuss mailing list [email protected] http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
