Silicon-on-insulator based modulators and switches for high speed optical telecommunications

This study investigates an out-of-plane optical coupling geometry into silicon-on-insulator (SOI) technology in order to create data transmitters and receivers for optical communications wavelengths. This geometry can, in principle, provide both high switching contrasts and high speeds. The study is carried out in SOI waveguides equipped with optically-resonant periodic electrode (ORPEL) structures, developed using conventional microelectronic fabrication techniques. As a receiver, the periodic electrodes enable the device to selectively couple a narrow band of light energy into the waveguide structure. As a transmitter, data to be transmitted from the device is imposed on a reflected signal from an incident continuous-wave probe signal; modulation is controlled by electronically altering the free-carrier density and/or distribution, thus altering the effective index of refraction of the waveguide core and coupling properties of the device. Initial optical and optoelectronic test results are presented.