Distributed effects model for cascaded traveling-wave electroabsorption modulator

A distributed model based on the large-signal electrooptic conversion is proposed to analyze cascaded traveling-wave electroabsorption modulators (TWEAMs) for high-speed optical switching applications. The microwave propagation loss, velocity mismatch, as well as frequency chirping are included. The model predicts that a cascaded TWEAM structure has the advantage of a high design tolerance to various distributed effects and an improved extinction ratio and optical loss in comparison to a single device of same total length. The agreement between experimental and calculated results indicates that the cascaded structures can be implemented for efficient TWEAM design.