Microwave Performance of Undercut Active Region for Traveling Wave Electroabsorption Modulator

A method based on undercut-etching-active-region is proposed to enhance the high-speed performance of the traveling wave electroabsorption modulator. It is found that increasing the widths of p-and n-cladding layer with the same i-layer to reduce the resistances in p-i-n waveguide can improve the microwave propagation loss and thus the high-speed electrooptical response.