We demonstrate optical bistability on a silicon-based integrated optical device. Hysteresis curves and modulation measurements show bistable modulation depth of 10 dB and sub-microsecond time response.
We demonstrate, for the first time to our knowledge, optical bistability on a highly integrated silicon device, using a 5-microm-radius ring resonator. The strong light-confinement nature of the resonator induces nonlinear optical response with low pump power. We show that the optical bistability allows all-optical functionalities, such as switching and memory with microsecond time response and a modulation depth of 10 dB, driven by pump power as low as 45 microW. Silicon optical bistability relies on a fast thermal nonlinear optical effect presenting a 500-kHz modulation bandwidth.
The characteristics of novel optical bistable devices which integrate both interdigital electrodes and amorphous silicon photovoltaic detectors on the Ti-diffused LiNbO3 waveguide are described. In the devices, the transmitted light of the interdigital electrodes enters the amorphous silicon photovoltaic detectors and the output voltage of the detectors is fedback to the electrodes. Optical bistable operation occurs due to the nonlinear dependence of the transmission efficiency of the electrodes on the applied voltage. The characteristics of differential gain and hysteresis of the device were observed experimentally.