structure problem for wg and mode source
I have problem with my varFDTD simulation. I have a waveguide with refractive index of 2 surrounded by material of index 1.44. I can see the index structure through an index monitor as the following figure.
The right bar shows the max and minimum value of the index. The problem now is that the mode source does not see the same index profile. I put the source in the lower waveguide as seen in the following figure (white circles). When opening the source to select the desired mode, I cannot see the waveguide, and hence all wrong modes are generated
Do you have an explanation for that? how can I correct it?