Silicon Photonics (15/2) Yonsei University High-Speed Circuits & Systems Lab. Dept. of Electrical and Electronic Engineering Yonsei University Directional Coupler MODE Simulation Silicon Photonics (15/2) Yonsei University Lumerical MODE Solution FDE(Finite Difference Eigenmode) solver -Calculate physical properties of waveguide modes -Solve Maxwells equations for cross-sectional mesh 2.5D varFDTD(Finite Difference Time Domain) -Time domain simulation with approximation -2D simulation speed with 3D accuracy EME(Eigenmode Expansion) solver -Frequency domain simulation Silicon Photonics (15/2) Yonsei University Directional Coupler P through P in P coupled Coupling gap Coupling length Silicon Photonics (15/2) Yonsei University Structure Rib waveguide -Width : 500nm -Thick : 220nm -Slab : 130nm 130nm220nm Lower Waveguide Upper Waveguide Coupling -gap : 100nm -length : 1um Coupling length Silicon Photonics (15/2) Yonsei University Structure(Cladding) Silicon Photonics (15/2) Yonsei University Structure Code(Slab) Silicon Photonics (15/2) Yonsei University Structure Code(Waveguides) Upper waveguide Lower waveguide Silicon Photonics (15/2) Yonsei University FDE Solver Silicon Photonics (15/2) Yonsei University Simulation Result Silicon Photonics (15/2) Yonsei University 2.5D varFDTD -Time domain simulation with light propagation -Can monitor power at both through, coupled port Silicon Photonics (15/2) Yonsei University Simulation Setting Silicon Photonics (15/2) Yonsei University Source Setting Silicon Photonics (15/2) Yonsei University Monitor Setting Silicon Photonics (15/2) Yonsei University Simulation Result Silicon Photonics (15/2) Yonsei University Exercise