Reply To: Effective indices of first two modes in SWG

[Guilin Sun]

 

It seems something is wrong in the settings, as you can see, the FDE result shows that neff is about 2.81 for the fundamental mode at 1.55um. However in the bandstructure result, there is no data at 1.55um. Before it reaches 1.5um it curves.

It might mix the modes as it has two bands.I checked the sweep. You set the relative kx from 0.25 to 0.7, which is too large. The kx in the sweep (and the group) is the relative one. Please check the First Brillouin zone, and refer to the example.