Simultaneous tapering and crystallisation of silicon core optical fibres

Silicon photonics is an increasingly active and exciting research topic that owes much to the excellent optical material properties of silicon. Crystalline silicon has a high refractive index (~ 3.48 @ 1.5 mum), a low loss transmission window between 1.2 mum - 6.7 mum, and a large third order optical nonlinearity (orders of magnitude greater than that of silica) making it a highly attractive material for photonic device miniaturisation. A new class of silicon waveguide, the silicon optical fibre, consists of a silicon core and a silica cladding and offers new possibilities within silicon photonics. To truly exploit the nonlinear properties of this fibre, control over its waveguiding characteristics is desirable.