A Highly Birefringent Photonic Crystal Fiber with Three Rows of Circular Air Holes

An exceptionally high-performance, high-birefringent photonic crystal fiber (PCF) is meticulously designed. The core design features a unique arrangement in which the central row of circular air holes is substituted by three rows of smaller circular holes. Subsequently, the middle row is adjusted to achieve various rectangular mode field configurations. With the optimized structure parameters, the birefringence of the PCF can reach 3.57 × 10−2 at a wavelength of 1.55 μm. The confinement loss is as low as 8.4 × 10−6 dB/m. The nonlinear coefficient is up to 41 W−1·km−1. The dispersion is relatively flat within the range from 1.3 μm to 1.9 μm. These remarkable characteristics render the proposed PCF a strong candidate for applications in polarization preservation, dispersion compensation, wideband supercontinuum generation, and other related fields.