Properties of a novel hybrid hollow core photonic crystal fiber

We present a novel hybrid hollow-core photonic crystal fiber, which can confine and guide light in subwavelength-diameter air holes of core. The propagation mechanism of low-refractive-index hole is studied by evanescent field coupling and electromagnetic theory of optical waveguide transmission. The unique transmission characteristics in the novel fiber with new propagation mechanism are shown. The evanescent-field power fraction in the core holes can be changed flexibly between 10% and 50%. The confinement loss is very low in the broadband wavelength range 1-1.8 mu m, which is not limited by surface modes and photonic bandgap effect appearing in hollow-core photonic bandgap fibers. The excellent characteristics of matching mode area, high birefringence, single polarization and single mode in hollow-core fiber are obtained. The two-zero dispersion, broadband flattened dispersion and dispersion compensation properties of hollow-core fiber are also presented. The novel hybrid photonic crystal fiber has the characteristics of solid core fibers and is suitable for the application as hollow core fibers.