periodic structures

My team at the lab are having great difficulty at figuring out how to simulate photonic crystals in HFSS. We need to use spherical coordinates to set oblique light vectors towards our periodic structures. We cannot use radiating boundaries for this because they can only be used for perpendicular angles of incidence. Currently we are using a combination of pml and an airbox that souronds the object on both sides. We are not sure how to calculate the best airbox size for our simulations and seem to be getting bad results where our graphs are a little off everytime. Any help with figuring out what the problem is would be great. We are newbies at using HFSS.

I ve seen several ppt telling me to use a PML however when I used a PML the mesh building process (abc3d.exe) in HFSS usually went wrong. So I said Hell Whatever and tried not using PML --- only an air box covering ur unit cell and defind linked BC on the air box surfaces... It works well so far. The eigenmodes I got is consistent with the strcture's transmission diagram got from a waveport excitation method.

Actually I am trying to use dispersion diagram from HFSS to calculate density of states of photonic crystal. Anyone here has same experience to share with us?

And one question too: does one mode got from HFSS eigensolver mean one band? And usually the modes you get are very close to each other like mode 4 260.45GHz and mode 5 260.72GHz. How reliable could these results be? Maybe they are just the same modes?

Any advice would be helpful!

Why I can't download it?

Can anybody here help me?

Thanks,

Gao Bo

Try this link about Hfss.

https://www.edaboard.com/download2.php?id=83854