Coherence Properties of Supercontinuum Generated in Dispersion-Tailored Lead-Silicate Microstructured Fiber Taper

摘要

This article details the numerically studied coherence properties of the supercontinuum generated in a lead-silicate microstructured fiber taper, with an in-creasing core radius along the propagation distance that tailors the dispersion prop-erty. Simulations are conducted by adding quantum noise into the input pulse at 1.55μm, and the complex degree of first-order coherence function and the overall spectral coherence degree are both calculated. Although the spectral broadening is comparable, the coherence degree is shown to vary with different pumping conditions. It decreases with higher peak power and longer duration due to the significant compe-tition between the soliton-fission process and the noise-seeded modulation instability. By controlling the input pulse parameters, it is possible to generate a perfectly coherent supercontinuum with a flat broadened spectrum extending from ~1μm to ~5μm in this fiber taper.