How can I use user defined lossy metal in CST MWS?

Hello. I have a question.

I am using now CST MWS 2009 Frequency domain solver program.

At 633nm (optical wavelength),

I want to use the gold metal aperture in this wavelength region.

So, I have to make the new one using the normal material setting.



In normal dielctric material with loss, we can use the loss tangent delta.

For example,

e = 2.25 - i*0.02 then,

we put 2.25 to the epsilon box and we put 0.02/2.25 to the tangent delta.

I heard that it works well.



Now, I want to make the lossy metal material profile through same method.

In other words, complex epsilon of gold metal at the wavelength of 633nm is

-9.514-i*1.218.

then, we put -9.514 to epsilon and we put 1.218/9.514, 0.128, to the tangent delta

blank box.



is it right method?



I simulated some structure to confirm the accuracy.

most results are very similar(or same) to the published data.

But very few data is not same with the published data.



this is the point.

please give me a some information about it.

thank you very much.