Meta-coupler empowered dynamic wavefront control with on-chip polarization reconfiguration

Metasurfaces consisting of subwavelength structures have shown unparalleled capability in light field manipulation. However, their functionalities are typically static after fabrication, limiting their practical applications. Though persistent efforts have led to dynamic wavefront control with various materials and mechanisms, most of them work in free space and require specialized materials or bulky configurations for external control. This deviates from the original intention of metasurface to realize compact and integrated devices. Here, we leverage the on-chip geometric metasurface associated with polarization reconfiguration of the guided wave, enabling three functions simultaneously: guided wave radiation, polarization multiplexing, and dynamic wavefront manipulation. We demonstrate proof-of-principle functionalities, including intensity-continuously tunable multifocal metalens, and dynamic zoom metalens as well as dynamic holography, based on a metasurface dressed lithium-niobate-on-insulator waveguide. Such an integrated platform for dynamic wavefront shaping implies the prospect of advancements in chip-integrated multifunctional meta-devices.