Fabrication and characteristics of bismuth oxide based highly nonlinear fiber

Highly nonlinear fiber with step-index type and microstructure type were fabricated using Bi2O3 based high refractive index glasses. Step-index type fiber with effective core area of 3.3 μm2 was fabricated using core and cladding glass whose refractive index is 2.22 and 2.13. This fiber exhibits high nonlinearity (γ = 1300 W-1km-1) because of high nonlinearity of the glass material and the small effective core area. The fiber also exhibits low loss (-1.9 dB/m) and fusion spliceability to silica fiber. Microstructure type fiber which shows low GVD and high nonlinearity simultaneously was fabricated by a novel inflating method. This fiber has a guiding core structure to reduce the fusion splicing loss when air holes collapse. Wide wavelength tuning range due to small GVD in four wave mixing experiment was demonstrated.