Fig. 1: Illustration of the concept of all-fiber integrated angular demultiplexing using nanoprinted periodic structures on single-mode multicore fibers (left: input side, right: output side).

Note that two colored arrows refer to an incident light field that includes two beams with different angles of incidence that are coupled into two selected cores. The lower right inset shows an example image of a functionalized multicore fiber that contains a nanoprinted periodic structure on each of the cores (the white scale bar corresponds to a length of 50 μm).