We report the low-power optical bistability under the continuous wave pumping conditions in photonic crystal linear resonators containing the InGaAsP quantum well active medium. The threshold bistable power is measured to be 35 muW at the normalized detuning of -1.724, by employing fiber coupling techniques.
We demonstrate extremely low-power all-optical bistability by using photonic crystal linear resonators based on InGaAsP quantum-wells. Since the photonic crystal cavity has a high quality-factor and a small mode-volume, the photon density in the cavity is extremely high, which makes it possible to reduce the bistable power. The measured minimum bistable threshold power was 37 muW by using a fiber coupling technique, and the estimated nonlinear refractive index (n2) was -6.84times10-14m2/W at a wavelength of 1610.8 nm which is near the resonant wavelength of quantum-well. The low-power optical bistable operations in a single photonic crystal cavity open the possibility of integrated optical devices such as an all-optical memory and switch, based on photonic crystals
The authors report low-power optical bistability under continuous wave pumping conditions in five-cell photonic crystal linear resonators containing InGaAsP quantum wells, by employing the fiber-coupling technique. The threshold bistable power is measured to be 35μW at the normalized detuning of −1.724. Owing to the high band-edge nonlinearities of quantum wells and the efficient fiber coupling, minimal instability is observed. In addition, all-optical switching is demonstrated with switching energy less than 75.4fJ.
Optical bistability with low power and large modulation depth is observed in the silicon 2D photonic crystal 3 defect-long (L3) cavity coupling with a photonic crystal waveguide experimentally. The cavity-waveguide resonator system operates under the critical coupling condition. The triangular line shape of the cavity resonance and the hysteresis loop of the system is observed. The switching contrast is 7.7 dB and the modulation depth is 0.70 at the switching power of -12.1 dBm. A nonlinear coupled mode model is established to analyze the behavior of the cavity, and numerical simulation results are in good agreement with the experiment results.
We report on bistable operations in a microcavity formed on an AlGaAs-based photonic crystal slab at telecommunication wavelengths. We designed the cavity to achieve a high quality (Q)-factor, while maintaining a small mode volume; this was accomplished by removal of a single air hole. The fabricated microcavity exhibited a resonant peak with aQ-factor of 1900 at 1548 nm. In nonlinear transmission measurement, when the input power was increased, a bistable characteristic which was dependent on the detuned wavelength from the resonance was observed. The bistability was considered to originate from thermal nonlinearity due to two-photon absorption.