Integrated Optical Filter with Fast Electrically Reconfigurable Transfer Function

We demonstrate here an integrated optical filter based on lithium niobate, with fast electrically reconfigurable transfer function. The technique is based on phase-shift keying of the reflection Bragg grating in a waveguide. The transfer function can be favourably reconfigured by applying different combinations of electrical voltage to the electrode pairs on both sides of the waveguide. The time of reconfiguration is less than 1 μs.