Using COMSOL I am trying to find out modal overlap between TE00 and TE20 mode, only in the core area of a ridge geometry. It will be helpful if someone can provide me any hint to solve it out...
Modes of the same waveguide are orthogonal, so the overlap is zero per definition.
If you restict the overlap integration to just the core of the waveguide, it might be finite but small as the mode field drops outside the core very fast. What is teh sense of your calculation?
It is different when you calculate mode overlap of different waveguides.
Thank you for your answer. It is true that the modes are orthogonal, so the overlap will be zero in the entire region. But in the case of two symmetric modes, the overlap integration has some considerable value which we calculate to find out the coupling coefficient in case of a long period grating. I want to calculate that by using COMSOL.