Optimized 3-D simulation method for modeling out-of-plane radiation in silicon photonic integrated circuits

We present an accurate and fast 3-D simulation scheme for out-of-plane grating couplers, based on 2-D rigorous [finite difference time domain (FDTD)] grating simulations, the effective index method, and the RayleighSommerfeld diffraction formula. In comparison with full 3-D FDTD simulations, the rms difference in electric field is below 5% and...