Proposal for a new all-optical waveguide functional device

A new type of all-optical logic gate is described that employs a single-mode waveguide, unequal-arm-length Mach-Zehnder interferometer fabricated using materials that exhibit an optical Kerr effect. Because of the unique properties of the single-mode Y junction, there is no reflected light output from the element. This interferometer is therefore suitable for digital signal processing because an optical isolator is not needed for connection as a serial array to achieve sharp on-off characteristics.