GROUP VELOCITY DISPERSION CONTROL BY SUSPENDED- CORE SOFT-GLASS FIBER FILLED WITH CARBON DISULFIDE

An enhanced group velocity dispersion (GVD) control with suspended core fiber (SCF) has been investigated using numerical simulation based on the finite element method. It requires an SCF made of lead-bismuth-gallium-oxide glass with three air holes filled with carbon disulfide (CS2). Unlike unfilled fibers, CS2-filled SCFs can achieve small slopes of the effective refractive index curves using the fundamental modes, resulting in flat group velocity dispersion in the low group velocity region. We also found that the ratio between the width of the bridge and the core radius can affect the shift of the zero-dispersion wavelength. The proposed SCFs show excellent performance in achieving low anomalous GVD, which can offer higher efficiency in supercontinuum spectral flattening. Additionally, the structures with small normal GVD values are promising candidates for pulse stretching due to the exact balance between nonlinear effects and dispersion.