|Publication No: 4865||Search all ORC publications|
Micromachined multimode interference device in flat-fiber
S.Ambran, C.Holmes, J.C.Gates, A.S.Webb, P.G.R.Smith, J.K.Sahu
A novel flat-fiber platform is presented for fabricating integrated optical multimode interference (MMI) devices. Fabrication is achieved by modifying a standard optical fiber drawing process and applying a micromachining technique. The fabricated structure consists of an MMI region within the flat-fiber that is defined by micromachined trenches, illustrated in Figure 1(a). A 1x3 splitter has been demonstrated, with a spatial output mode that be tuned by placing refractive index oils within the micromachined trenches.
MMI devices have been demonstrated in different planar platforms such as silicon-on-insulator and silicaon-silicon. However, many of these materials are potentially expensive, high loss or have a complex fabrication process. The desire to have a fiber-like platform, capable of supporting multiple waveguides in a planar format, led us to develop a novel silica optical flat-fiber technology. This allows us to overcome the limitations of existing planar technologies by offering a low cost, low loss substrate with fiber-like flexibility, long lengths and the ability to make integrated devices. The flat-fiber substrate is fabricated using standard silica fiber fabrication but differs by collapsing the preform during the fiber drawing stage by using a vacuum. The trenches of the device were diced using an ultra-precision micromachining technique.
Photonics Global Conference Singapore Dec 14 - 16 (2010)
Copyright University of Southampton 2006