Micro-scale, whispering gallery mode (WGM) resonators are important devices for trapping, slowing down, and intensifying light in opto-electronic applications. Of the many available silica-based devices, surface nanoscale axial photonics (SNAP) resonators are a new generation of WGM microresonators, consisting of an optical fiber with nanoscale variations of its effective radius. They have received great attention owing to their advantages over conventional silica-based devices, such as flexibility and ultra-low losses, which lead to ultra-high quality factors. They have demonstrated great potential as photonic micro-devices in switching, slowing light, filtering, lasing, and sensing with high precision, as well as for research on Anderson localization and tunnelling.

In this thesis, we present a new fabrication method for SNAP devices using a regular hydrogen-oxygen torch, requiring less equipment than current techniques. We have characterized our SNAP devices with evanescent spectroscopy, utilizing a tapered optical fiber as an excitation source. The transmission spectroscopy results show that our  flame fabricated SNAP devices have modes with very high quality factors (~10^7) which can show significant thermal non-linear effects.