Broadband Single-Polarization Single-Mode Operation in Photonic Crystal Fibers With Hexagonally Latticed Circular Airholes

A photonic crystal fiber with hexagonally latticed circular airholes is designed to deliver single-polarization single-mode (SPSM) operation over a broad wavelength band. Base on a W profile and a triple-defect arrangement, such a design can provide an SPSM spectrum of ~1600 nm (from 0.406 to 2.304 μm) with confinement loss lower than 0.01 dB/km. To the best of our knowledge, this is the broadest to date for a hexagonal lattice with all circular airholes, which can be realized by the simple “stack and draw” process. In favor of the broadband operation, the adjustment of structural parameters allow the dispersion engineering for a flattened behavior within a certain SPSM window, which is highly desired in communication systems, as both the chromatic and polarization-mode dispersions can be radically eliminated.