Optical pulse controlled all-optical logic gates in SiGe/Si multimode interference

An optical pulse controlled all-optical logic gate with multifunctional performance and asymmetric structure has been designed theoretically in SiGe/Si materials using multimode interference principle. By switching the optical signal to different input waveguide ports, the device can function as OR, NOT, NAND, and NOR gates simultaneously or individually. It is a kind of promising device for next generation logic optical circuits, ultrahigh speed signal processing, and future Si-based all-optical integrated circuits.