Variable Demultiplexing Using a Twin-Core

A novel form of demultiplexer is demonstrated us- ing a single untapered length of twin-core fiber. The degree of demultiplexing can be vaned so that an arbitrary amount of power at a given wavelength (e.g., 13 pm) can be removed from a multiplex to two wavelengths (e.g., 13 / 1.55 pmh The varia- tion is achieved by locally bending the fiber in the plane of the twin cores. Channel spacings of 30 nm have been achieved experimentally.