Quantitative analysis of optical reflection in a multimode interference 3 dB coupler using a low-coherence interferometric reflectometer

摘要

The quantitative reflection characteristics of multimode interference (MMI) couplers are investigated using a low-coherence interferometric reflectometer for the first time. MMI couplers are fabricated in an InP/InGaAsP/InP double-heterostructure, and the reflectivity from the interface between the MMI region and output waveguide is shown to be >-30 dB.