Specialty Optical Fibers Handbook

optical wave-guiding in subwavelength–width waveguides [50–53]. This section

focuses on taper-drawing fabrication of silica nanofibers.

11.4.1 Two-Step Taper Drawing of Silica Nanofibers

The fabrication of thin silica fibers using a high-temperature taper-drawing

technique was first reported in the nineteenth century, when the mechanical

properties of the fibers were studied, but their optical properties and applications

remained uninvestigated [54, 55]. It was not until a century later, when optical

waveguide theory had become well established, that researchers began to inves-

tigate the optical applications of very thin silica fibers made by laser- or flame-

heated taper drawing of optical fibers [56–60]. Laser heating provides highly

stable and