Why my T value is larger than 1

fdtd

#1

Hi,
I am working on the simulation of transmission holes. I followed the example sp_array and played with the parameters. I got a resonance peak. However the T value is about 3. Should it be smaller than 1? Since T is a normalized value? I uploaded the file below. Does anyone have any ideasample3.fsp (1.2 MB)
what’s wrong with my design? Any help would be appreciated. Thanks


Why my T value is larger than 1
#2

Dear @zyy0417

Thank you for reaching out.

It looks like you are using a mesh override region with really coarse mesh of 50 nm. Also, the geometry of the mesh doesn’t seem very appropriate as it covers almost the entire simulation region. I guess you need to change the geometry to include only Au and use finer meshes such as 5 nm (as your gold layer is 50 nm). This should solve the weird results that you were seeing. The nanohole array example in KB will be a very good place to learn more about this sort of simulations.


#3

Dear @bkhanaliloo
Thanks for your help. I was learning from the example. I followed your suggestions and also changed the pml to steepangles. The problem was solved in this way. Thanks.