Post-Processing of Optical Fibres Through Tapering and Nanostructuring
Takasugi, Eric H.
- The purpose of this thesis is to explore how the properties of an optical fibre can be changed to expand on their utility. This includes both giving fibres new properties as well as enhancing pre-existing ones. These can be done by altering the dimensions and geometry of the fibre or by changing the media in and around the fibre faces. This thesis explores all of these aspects: optical components ... read moreare affixed to the end of certain fibres; heating and pulling is used to affect the geometry of some fibres. All of these are tested and their effects on the fibre are explored. The first process, silk imprinting, investigates the ability to imprint nanostructures (in this case, a grating) onto the fibre face. This will allow us to imprint periodic or aperiodic structures on fibre faces in a material which can be implanted in the body with no negative effects. Thus, we can implant even fibre optics (coupled with current work in silk optical fibre) in the body without the body rejecting the implant. Tapering works to increase the nonlinear effects by decreasing the core area. As will be discussed, the core area is closely tied to the nonlinear effects in the fibre. Furthermore, if the nonlinear effects can be generated with shorter amounts of fibre, then a supercontinuum source can be made entirely out of fibre and therefore can be portable. Tweezing beads into an optical fibre introduces a periodic glass structure into the end of the fibre. This could allow us to tune the spectrum coupled into the fibre. Furthermore, the ability to tweeze into the fibre core would mean that other materials could also be tweezed to affect the light traveling through the fibre.read less