A design study of a Ti:LiNbO/sub 3/ traveling-wave electrooptic modulator by the finite element method

This work presents the analysis and design of electrooptic modulators by the finite element method. The propagation characteristics of E/sup x/ modes (effective index, optical field profiles and spot size) in Ti:LiNbO/sub 3/ waveguides as a function of manufacturing parameters and the quasi-TEM wave characteristics (effective dielectric constant and characteristic impedance) for the coplanar waveguide are computed and shown. Two x-cut Mach-Zehnder-like modulators are analyzed and compared. The first one presents a conventional electrode configuration and the second one is a modified configuration which includes a set of floating electrodes.