Fan-out device for multicore fiber coupling application based on capillary bridge self-assembly fabrication method

•We utilize a method based on capillary-bridge force self-assemble technique to fabricate the fiber arrays for the fan-out devices of the multicore fiber.•We unifies the analysis method of the relations between coupling errors (transverse misalignment, longitudinal misalignment, angle misalignment) and coupling efficiency, and verify it through simulations using a BeamProp software.•We propose an efficient coupling process for multicore fiber and other optical waveguides.

In this paper, a fan-out device for multicore fiber (MCF) based on capillary bridge self-assembly fabrication method is proposed. The relation among the coupling errors (including transverse misalignment, longitudinal misalignment, and angle misalignment), refractive-index match and the coupling efficiency is analyzed in theory and simulation, and the transverse misalignment and angle misalignment are found to be the main factors affecting coupling efficiency. Then, a fan-out for a four-cores MCF is fabricated by using capillary-bridge force self-assembly of the UV adhesive, the coupling process of fan-out for four-cores MCF, consisting of transverse alignment, longitudinal alignment and tilt alignment, is demonstrated through the coupling of one core to the coupling of two cores, until the coupling efficiencies of all cores are the maximum. At last, the coupling loss of the packaged fan-out in the 1.55 μm spectral region is measured, and the actual coupling loss of all cores is less than 1.25 dB.