▎ 摘　　要

NOVELTY - The fiber has a medium hole provided with a non-central medium hole (2), a central inner medium hole (3) and a central outer medium hole (4). A substrate material is provided with a double-core region (5). The non-central medium hole is arranged in seven layers along X axis direction on the substrate material. The double-core region is formed by deleting fourth and sixth medium holes from a central position of a base material (1) along the X axis direction. An annular gap is formed between the central inner medium hole and the central outer medium hole. A central medium ring is filled with graphene. USE - Ultra-wideband double-core photonic crystal fiber for manufacturing a polarizing beam splitter. ADVANTAGE - The splitter is simple in structure and small in size, and has high light splitting ratio and wide working band, and can change optical fiber structure parameter by external factor so as to reduce influence on performance of the splitter. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of ultra-wideband dual-core photonic crystal fiber. Base material (1) Non-central medium hole (2) Central inner medium hole (3) Central outer medium hole (4) Double-core region (5)