Nanoelectromechanical-systems-controlled bistability of double-coupled photonic crystal cavities

In this Letter, we report an approach to controlling the bistability of double-coupled photonic crystal cavities with a nanoelectromechanical comb drive, in which the optical force and thermo-optic effect form a feedback mechanism to the effective index of the cavities, and the gap width between the cavities is steered by the comb drive. A model based on temporal coupled mode theory is established to analyze this approach. Hysteresis loops characterizing the bistability are experimentally achieved by sweeping the gap width forward and in reverse. In addition, the experiments also demonstrate that the bistability is tunable by varying the input light power.