Reply To: Waveguide Sims (FDTD vs varFDTD)

[Ethan Keeler]

Hi Amogh,

It's a bit difficult to diagnose the issue without being able to directly consider your simulations files; however, here are a few topics to consider:

1. The MODE Source span should be large enough such that the fields have decayed to ~1E-05 of the peak value at the edges. This will avoid significant clipping of the mode energy.
   
   
2. We also recommend that there is a lambda / 2 distance from the source to the PML boundaries.
   
   
3. The mesh accuracy of 4 seems pretty reasonable already, but you could try increasing it to 5 to see if there is a significant change in the result. This will allow you to do a bit of convergence testing on the result to find the best choice for the mesh. You could also add index monitors in your two simulations to see how resolved the bend is.

Hopefully some of these pointers can help in reconciling the two simulations.

Ethan