High-reflectivity monomode-fibre grating filters

Abstract

The fabrication and characterisation of efficient, narrowband fibre-optic filters utilising surface-relief gratings etched into monomode fibre are described. A device with 92% reflectivity and 1·8 nm bandwidth at 1·3 μm wavelength using a first-order Bragg grating with a high-index overlayer is reported.