Tapered Waveguides Improve Fiber Light Coupling Efficiency

Silicon waveguides have strong light confinement properties due to a very high index core (silicon, refractive index ~3.5) material surrounded by a much lower index glass (silica, refractive index ~1.5) cladding. Due to this property, silicon waveguides can turn light paths through sharp bends without suffering any appreciable loss. This enables miniaturization of functional optical components and enhances dense integration of devices on waveguide chips.