A circular ultra-short $A{s}_2{S}_3$ filled double-core photonic crystal fiber polarization beam splitter is proposed. The finite element method is used to study the performance of the designed photonic crystal fiber polarization beam splitter. By filling high refractive index $A{s}_2{S}_3$ into the central air hole, the coupling performance of the double-core PCF is improved. By optimizing geometric parameters, the splitting length of the circular beam splitter can be as short as 72.43 $\mathsf{\mu }$m, and the extinction ratio can reach −151.42 dB. The high extinction ratio makes the circular polarization beam splitter have a good beam splitting function. The designed circular double-core photonic crystal fiber has the same cladding pore diameter, which is easier to prepare than other photonic crystal fibers with complex pore structure. Due to the advantages of high extinction ratio, extremely short beam splitting function and simple structure, the designed polarization beam splitter will be widely used in all-optical networks and optical device preparation.

A method of preparing panda-shaped photonic crystal fibers (PCFs) based on secondary drawing technology is proposed in this paper. The secondary drawing can not only reduce fiber diameter but also reduce core size by adding a glass sleeve. Silver-filled and non-silver-filled panda PCFs are prepared. The two ends of silver-filled panda PCF are connected with a broadband light source and a spectrometer, respectively, and the surface plasmon resonance phenomenon is detected. The secondary drawing technology provides a meaningful reference for the preparation of PCF in the future, and the prepared silver-filled panda PCF can be prepared into an optical fiber filter.