Crossing-channel waveguide electrooptic modulators

This paper presents a general theoretical investigation of the integrated-optical crossing-channel waveguide electrooptic modulator (sometimes called a "TIR" modulator). The theoretical model is based upon the analysis of mode conversion during propagation through the device. The theoretical results are compared to experimental data. The operation of these modulators can be roughly divided into two classes, reflective-type and mode-interference-type devices, based upon an "adiabatic criterion" (made up of the optical wavelength, the waveguide width, and waveguide crossing angle) and upon the number of modes supported by the waveguide.