Two-dimensional propagating beam analysis of an electrooptic waveguide modulator

Diffused waveguides are analyzed employing the propagating beam method. By reducing the problem to two dimensions by the effective index method, a reduction of the computer time by a factor of 100 is achieved. The method has been exemplified by aY- branch electrooptic waveguide modulator. The calculated output power versus applied voltage is in good agreement with results found in the literature. We expect the method to be a powerful tool when optimizing the geometry of modulators and similar waveguiding circuits with respect to physical dimensions and losses.