Hybrid silica nanowires with a highly nonlinear glass think coating

We report on the fabrication of hybrid photonic nanowires consisting of silica tapered fibers covered with a thin layer (<; 100 nm) of a sol-gel derived highly nonlinear glass (HNG). These hybrid nanowires exhibit finely tunable waveguide properties: The deposition of a single layer of high index glass around the silica taper is found to be sufficient for obtaining zero-dispersion operating wavelengths at any point throughout the visible to mid-infrared range, while both positions and values of dispersion maxima can be adjusted according to design. It is, thus, possible to fine-tune the waveguide properties of the nanowires only by slightly adjusting, for example, the thickness of the HNG layer, while keeping the silica taper diameter constant.