Elliptical-spiral elliptical-hole photonic crystal fiber with high birefringence, large nonlinearity, and two zero...

This paper presents a soft-glass (SF-57) elliptical-spiral photonic crystal fiber with elliptical air holes for achieving high birefringence, large nonlinearity, and tailoring two zero-dispersion wavelengths (ZDWs) in the near-infrared region. A full-vector finite-element method with perfectly matched boundary layer is used to characterize the properties of the photonic crystal fiber for different ellipticity ratios. The designed fiber has a birefringence 4 times higher than the circular-spiral structure. There are two ZDWs at around 1.2 µm and 2.8 µm which can be finely tuned depending on the ellipticity ratios along with a large nonlinearity. Due to the superior guiding properties, the proposed structure can be used for polarization control and broadband supercontinuum generation.