Why the index of the waveguide (input wg, output wg top, output wg bottom) in ‘y_branch_base_TE_modematch.lsf’ (FDTD 2D simulation) is seted as 2.8? Does that mean the refractive index of the silicon slab with a thickness of 220nm is 2.8? Could you give me some reference papers? And what’s the exact meaning of the scalar ‘index’ in material and why the index has a length units?
Fig.1 material setting for input wg
y_branch_base_TE_modematch.lsf (2.2 KB)
If I want to set the source mode as the following higher order mode (TE1), are the settings of the material in this waveguide same as Fig.1?