Tunable optical bandpass filter with multiple flat-top bands in nanostructured resonators

摘要

Based on second-order nonlinearity, we present a tunable optical bandpass filter at oband by introducing a back quasiphase-matching technique with a nanostructured named multiple resonator waveguide. Two injecting forward lights and one backward propagating light interact with difference frequency generation. At that juncture, the transmission of the forward signal can be modulated via changing the forward control power. As a result, a tunable optical bandpass filter with multiple flattop transmit bands of the forward signal can be formed in the waveguide.