IBM’s Optical Modulator
Date added: 06 Dec 2007
IBM’s optical modulator uses “silicon nanophotonic waveguides,” to control the flow of light on a silicon chip. The waveguides are made of tiny silicon strips (marked by purple color) with dimensions 200 times smaller than the diameter of a human hair, in a silicon-on-insulator (SOI) wafer. Digital electrical signals are applied to the p+-i-n+ doped silicon nanophotonic waveguide through the electrodes (marked by gold color). Electrical charges (holes – green particles; electrons – red particles) are injected into the waveguide and change the optical properties of silicon, which is used to perform the modulation function.