Multi-element fiber for next generation optical communication

We review Multi-element Fiber (MEF), which comprises multiple fibers coated together in a common polymer coating, for applications in space-division multiplexing (SDM) system. MEF geometry doesn't require any special MUX/DEMUX devices to access each fiber-element and conventional splicing techniques can be used to integrate MEF with other optical devices. Development of both passive MEF for high capacity optical transmission and Er-doped wideband MEF amplifiers both in core and cladding pumped configurations will be presented.