Subnanosecond Opto-electrical Switches Based on a Domain Inverted Wavegulde Directional Coupler with a Uniform Traveling-wave Electrode

Conventional electro-optic (EO) switches must have multiple electrode sections to ensure a producible polarization-insensitive device, which is impractical for high-speed operation and compact device integration. There have been great advances in achieving high-frequency operation using phase reversal traveling-wave electrode structures. However, the presence of phase-reversal configuration in the electrode requires the fabrication of specially-structured thick electrodes to reduce the microwave loss, which is extremely difficult in fabrication. Moreover, these devices are polarization sensitive making the system integration difficult. A drastically new sub-nanosecond opto-electrical switch structure, based on a domain inverted wave guide directional coupler and a uniform traveling-wave electrode, is introduced, which will improve the switch performance in polarization insensitivity, switching speed, optical extinction ratio and polarization-insensitivity with a simplified fabrication scheme, leading to a higher reproducibility of the devices. Furthermore, employment of reliable opto-electrical polymer thin films (Dispersive Red 19 and LD-3 from Ad Tech) can be realized on any substrate of interest which significantly eases the implementation of the high speed optio-electrical switching devices for the US Navy's Optical truetime delay lines. The domain inversion in EO polymers is expected to be much easier to be made on account of the thin film characteristic (<10).