Learning Forum

[schinta3]

Hello,

I would like to use the new RWCA solver recently released, and have some questions on the geomertry structure that needs to be passed.

1) Can i export an existing FDTD model to the requred strucutre format?

2) I have an irregular import object. Is it possible to convert this to the structure needed,?

3) Do I only need 1 unit cell of the crystal for the rwca to work (i.e. does it automatically sense the boundary conditions, etc, as the example seems to only have 1 unti cell.

[Kyle]

The RCWA uses the geometry in the FDTD CAD, so you should be able to use the same geometry from your FDTD simulation in the RCWA simulation without modifying it (assuming the edges of the unit cell are aligned with the x, y, or z axes).
The geometry used by the RCWA solver is the same type of geometry used by FDTD, so if you can import it into FDTD using one of FDTD's geometry import options, it can be used with the RCWA solver.
Yes, only one unit cell is needed.

[schinta3]

Hello Thank you for this information. However, I still have a question. In the example script, the entire shape is added to the simulation region programmatically.
How do I call an existing set of model>structures into the rcwa function.

[Kyle]

In the example the structure is added to the FDTD CAD through script commands, but the end result is the same as adding them through the buttons in the GUI. How the structure was created doesn't matter, the RCWA solver will use whatever geometry is in the CAD, the same as FDTD. You don't need to do anything to create a geometry specifically for the RCWA solver. When you run the RCWA script command you specify the locations of the max and min boundaries of the unit cell and the RCWA solver will use whatever geometry is in that region in the FDTD CAD.

[schinta3]

Hello
Thank you for your help. I am working with the following file, and script. It seems that there are no 'periodic' residences , such as in the example, literature, or other RCWA/FMM spectra. This actually seems to be treating the import as a solid block of the absorptive material. Do you have any recommendations?

Best Sreyas

[schinta3]

I apologize. I can send a copy of the .fsp and .lsf file if neeed via email, etc.

Best Sreyas

[Kyle]

Sorry for the delay in replying. Are you referring to the same simulation as your post here?
If you are, maybe we should continue the conversation there to keep things organized.

[schinta3]

Hello
Yes it is the same type of simulation, however I can't seem to post the actual fsp/lsf file here. Is there some way to send that over?

[schinta3]

Hello
1 more quick question. If there are multiple unit cells defined in the geometry, will the solver behave in the same way?