Nonvolatile silicon photonic MEMS switches enabled by van der Waals force

The rapid development of artificial intelligence has catalyzed substantial progress in photonic information processing, which requires ultralow-power photonic switches for extensive circuit reconfiguration. Nonvolatile switches with zero static power are promising, but current phase change material approaches face challenges including unreliable durability, high switching energy, complicated fabrication, and compromised scalability. Here, we propose and demonstrate a nonvolatile silicon photonic microelectromechanical system (MEMS) switch enabled by tailored stiction effect based on van der Waals (vdW) force. The device uses a unique split waveguide crossing (SWX) with a push-pull MEMS actuator to efficiently switch the mode propagation. The vdW force between two halves of the combined SWX with zero gap provides reliable nonvolatility. The device features 0.23-decibel excess loss, 44.4-decibel extinction ratio, 200-nanometer bandwidth, and ~1-picojoule theoretical switching energy. Furthermore, excellent scalability is validated by a fabricated high-performance 16 by 16 nonvolatile photonic switch array, which has never been reported before.