On-chip electrically reconfigurable diffractive element and metalens with phase change material

Realizing compact, reconfigurable on-chip meta-atoms capable of dynamically controlling the phase and amplitude of integrated photonic fields remains a fundamental challenge. Here, we demonstrate a reconfigurable on-chip diffractive element and corresponding metalens based on the phase change material Sb2S3, enabling dynamic modulation of the optical field. Initially, a reconfigurable on-chip diffractive unit was designed by harnessing the intrinsic characteristics of the phase change material. Subsequently, an on-chip metalens was constructed from an array of these units, and state-of-the-art micro- and nanofabrication techniques were employed to realize the device. Finally, performance evaluations confirmed the metalens's reconfigurability. This provides a platform for on-chip reconfigurable photonics, with potential applications in photonic computing, optical storage, and advanced spectroscopy.