Tellurite Photonic Nanostructured Fiber

In this paper, we address the challenges faced in the fabrication process of nanostructured fiber. We show that a slight nonuniformity of holes of the preform results in a difference in the added pressure in the holes of the fiber during the fabrication process. It may not be a notable problem for the microstructured fiber, but it can result in serious deformation or even collapse for nanostructured fiber. By using a model, we propose a distortion factor that indicates the distortion degree of the geometry of fiber compared with the geometry of preform. The hole size of preform is the most important variable to the distortion factor. A large hole size in the preform is of great significance in decreasing the distortion. We also show that when the temperature is increased, the surface tension is decreased, but the viscosity is decreased much more quickly, so the distortion becomes severe. For minimum distortion in the nanostructured fibers we demonstrate, preforms with comparatively large and uniform inner holes are fabricated by inflating with inert gas. By using such preforms, we fabricate hexagonal core and triangular core nanostructured fibers with the smallest size recorded. Supercontinuum generation from the nanostructured fiber is demonstrated. In this paper, the glass we use for the demonstration is a soft glass. By using polymer or silica glass, which is more suitable for nanostructure fabrication, and by controlling the uniformity of holes in the original cane more accurately, various nanostructured fibers with even smaller size and more complex structure, or nanowire array, should be able to be fabricated by the inflation method.