Design and performance of multicore fiber optimized towards communications and sensing applications

Abstract

We report on the rapid prototyping platform, developed at Fibercore, for producing spun multicore fiber (MCF) which maintains the high-specification and quality of a large-scale manufacturing process adding the versatility to fully customize fiber for specific applications. Such MCF has been produced by using an ultrasonic drill to accurately position the core holes in the cladding glass, achieving <0.4µm accuracy in fiber. Cross-talk between cores has been minimized by implementing high numerical aperture cores of 0.20, with levels less than -55dB over 400m. Additionally, the high level of germanium doping also allows fiber Bragg gratings (FBGs) to be written into each core without the need for hydrogen loading. Finally, in order to enable distinction between any potential twist and strain in the fiber from the bend under measurement, a permanent twist has been introduced in the fiber by spinning the preform whilst it is being drawn. The manufacturing cycle time for the fiber is 8 days, allowing rapid prototyping and repeat development cycles to be tested over a short period of time when creating new fiber designs.