Analysis of the Precision of the Transfer Matrix Method Applied to Optical Coupling Problems

The Transfer Matrix Method (TMM) is widely used to efficiently simulate multi-layer optical structures. Considering the effective refractive index of guided modes, the TMM can be applied to calculate the optical coupling of Photonic Integrated Circuits (PICs). This manuscript describes the analysis of the precision of a new TMM model adapted to edge coupling simulation. The results are compared with full-wave electromagnetic simulations and the similarity between the two methods is assessed. The results show that the TMM can calculate coupling reflectances as low as -40 dB with less than 2 dB of difference compared to the electromagnetic simulation.