Simulation of Light Coupling Reciprocity for a Photonic Grating

V. Kivijärvi[1], M. Erdmanis[1], I. Tittonen[1]
[1]Aalto University, Department of Micro- and Nanosciences, Espoo, Finland
Published in 2013

SOI (Silicon on Insulator) technology utilizes silicon components on SiO2 layer. Propagating electric field distribution in a SOI waveguide is called mode of the waveguide. Photonic gratings are formed by etching grooves on the top of a waveguide. Gratings can operate in two directions. They can guide incident beam into a waveguide or a waveguide mode out of the structure.

We study the grating operation by utilizing optical reciprocity, which manifests that coupling of light between a waveguide and an optical fiber should not depend on the propagation direction. This principle allows for study of operation in two directions and determination of the coupled and lost power. Acquired knowledge is used to optimize the grating geometry.