Suppression of stimulated Brillouin scattering ina fibre bychanging the core radius

Stimulated Brillouin scattering (SBS) in a fibre is suppressed by making the core radius nonuniform along its length to utilise the core-radius dependence of the longitudinal acoustic frequency. The effective Brillouin gain of an SBS suppression fibre prepared by the VAD method was reduced by 3.5 dB compared with conventional fibres.