Looking for the best numerical software

hi
can anyone say which numerical software would be best for the simulation of nonlinear optics.i like to look into the nonlinear properties of photonic crystal and metamaterial. Fullwave do not give good result as it become unstable after few calculation.
plz mention some reference if y ou know.

I think Matlab is good simulator soft.

Due you′re regarding electronic components the use of PSPICE may be considered beacuse it can work directly with part models.

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