Off-level sampling method for bias stabilisationof electro-optic Mach-Zehnder modulator

A new method for stabilising the bias of an electro-optic Mach-Zehnder modulator has been developed to maximise the switching extinction ratio in burst mode packet traffic. By sampling and minimising the off-level output power of the modulator, a high extinction optical gate switch is obtained regardless of the variation of the packet traffic density.