Adiabatic coupling in tapered air-silica microstructured optical fiber

We study adiabatic mode propagation in tapered air-silica microstructured optical fibers and demonstrate efficient coupling into a robust high-delta microstructured optical fiber. As an application of this device, we exploit the widely flattened dispersion and enhanced peak intensity in the waist of the tapered microstructured fiber to generate tunable self-frequency shifting. Raman solitons over the communications window from 1.3 /spl mu/m to 1.65 /spl mu/m.