Adiabatic Mode Conversion in Multimode Waveguides Using Computer-Generated

We propose a mode converter based on adiabatic evo- lution of thesystem eigenmode.Mode conversionismediated by an intermediate mode that is hardly excited. The coupling properties are analyzed using the coupled-mode theory. Computer-generated planar hologramsonmultimodewaveguidesare designedto imple- ment the required coupling coefficients between the guided modes. Beam propagation simulations are used to verify the theoretical analysis. Index Terms—Coupled mode analysis, gratings, multimode waveguide.