Photonic band structure_Triangular lattice using CST/HFSS

Hi all

i have determined the band structure of square lattice for Metallic PBG using CST and HFSS both. But i am not understanding hw i can determined the band structure for Triangular lattice for the same. what sould be unit cell type taken and how phase change is considered? some what similar problem is asked before in this topic

https://www.edaboard.com/viewtopic.p...ght=triangular

Plz suggest me.........
Thanks in Advance

Hi there

can you post the details how you solve the square lattice problem using CST ?

regards

Dear Shahid,
You can see the following link for sauare lattice simulation........
https://www.edaboard.com/viewtopic.p...&highlight=ebg

Hi Ashubhu

thanks for your posting the link but i have seen this before and have made comments on that post as well

they have only posted a part of the dispersion diagram and not complete.

this is the problem i havent seen anyone successfully simulated dispersion diagram of metallic EBGs in CST and the reason is you cant use radiation boundary conditions in eigen mode solver of CST

i hope now you understand the underlying problem in CST

let me know if you have some other information which i dont know

regards

Hi shahid

i have done dispersion diagram of square metallic lattice by taking unit cell and defining boundaries of unit cell as periodic in the direction of periodicity and other one is as Electric (Et=0 )or Magnetic (Ht=0) using CST Eigenmoed solver(as it is done in given link above). I have not used radiation boundary anywhere. For triangular lattice i am not getting, hw it can be done?

Hi there

well this is what i am asking.
how can you generate a dispersion diagram without using radiation boundaries even for square lattice.

are you sure the results you got for square lattice are correct ?

i think if you post the model for square lattice and your simulated dispersion diagram then we can discuss how this could be done for triangular lattice. asi think finding the unit cell for triangular lattice should not be a problem

regards

hi Ashubhu
avoiding more chating without any activity
upload your model in CST ,i may help you more active
regards
regards to akhy shahid78

Hi all,

Here i am attaching my CST model for Square metallic lattice Dispersion. This is for TE mode. This is for only one region of the dispersion diagram. Plz suggest me model for triangular lattice.............

Hi Ashubhu,
Plz upload your triangular structure, paper from which you taken it and the results you want to match. I'll then check it and let you know.

Regards
Praful

Hi ev b'dy

Here i am attaching a paper in which triangular lattice and dispersion is given and i want to match it with using CST/HFSS. Till now i have not able to find the dispersion for it. Plz help me..........

thanks

Hi Ashubhu,
i'll take a look on it today.

Regards

Hi Ashubhu. Were you able to solve this problem for the triangular lattice? Please post your results and code. Also, how do you define the source? If you use periodic boundary conditions, the plane wave will be out of phase with neighboring unit cells when k is not zero. Please help.

Added after 3 minutes:

Hi Ashubhu. Were you able to solve this problem for the triangular lattice? Please post your results and code. Also, how do you define the source? If you use periodic boundary conditions, the plane wave will be out of phase with neighboring unit cells when k is not zero. Please help.

Hi all,

Anyone Plz reply soon. i need solution of this problem?

Hi all
No reply from anyone since long time.............plz do reply

Hi Ashubhu,

As you said before your configuration of your unit cell with periodic conditions is good.
However for the upper boundary condition, you have to used Electric or magnetic condition. If you do that you will plot the dispersion diagram of your structure in a cavity and that's not what you want (because you will obtain several reflexions due to the electric/magnetic condition).
So you need to increase the upper Z distance in the background properties to move away the upper boundary condition: generaly i use a upper Z distance of 27*height of the substrate BUT you have to do some test about it.

Try it and let me know about your future results (or problems).

regards

piboo

Hi Ashubu,can you send me the square lattice structure to this mail id please bandaru.ramakrishna@gmail.com