Reprogrammable Bistable Metasurface for Arbitrary Electromagnetic Wave Manipulation.

Mechanically reconfigurable metasurfaces have been designed to achieve continuous modulation of electromagnetic responses through the integration of deformable elements with structurally simple architectures. Although current implementations with independently addressable deformable units enable multifunctionality, their constrained phase modulation range imposes fundamental limitations on achieving fully reprogrammable metasurfaces. Here, we report for the first time a 1-bit phase-coding concept of a deformable unit based on the controllable interference of two three-dimensional (3D) bistable antennas, while maintaining superior broadband performance. By employing a hollow hyper-elastic substrate, we create a reliable platform for 3D buckling and shape switching of antennas, where out-of-plane loadings applied to each unit allow programming of the desired phase patterns. A reprogrammable metasurface prototype is meticulously designed and fabricated, demonstrating reliable, repeatable, and arbitrary functionality-switching capabilities. This concept establishes a robust foundation for mechanically reprogrammable metasurfaces and opens broader possibilities for applications in adaptive imaging, mechanical sensing, cloaking, information processing, and beyond.