End-Output Coupling Efficiency Measurement of Silicon Wire Waveguides Based on Correlated Photon Pair Generation

A method to measure the end-output coupling efficiencies between silicon wire waveguides (SWWs) and optical fibers is proposed and demonstrated. The end-output coupling efficiency is calculated through four measured counting rates based on the correlated photon pair generation in the SWW. It provides a way to investigate and optimize the coupling processes at the input and output end of the optical waveguides separately.