MEMS-tunable topological bilayer metasurfaces for reconfigurable dual-state phase control

• DOI: 10.1364/optica.529075
• Publication Date: 2024-10-15T14:59:03Z
• Authors: Chao Meng; Paul C. V. Thrane; Chuanshuo Wang; Fei Ding; Sergey I. Bozhevo...
• Keywords: 0301 basic medicine; 03 medical and health sciences

Tunable optical metasurfaces (MSs) have demonstrated exceptional capabilities in actively manipulating light fields. However, most existing tunable MSs are limited to controlling only one functionality. Here, by combining a MEMS mirror with plasmonic bilayer MS (BMS), we develop an electrically driven MEMS-BMS platform enabling complete reflection phase transformation and switching between two encoded functionalities actuating the mirror. This capability stems from different responses of each layer at distinct separations, due evolving topological singularities defined parameter space. With this platform, demonstrate polarization-independent for reconfigurable diffraction gratings, achieving ∼25% efficiency, ∼0.75 contrast 850-nm wavelength, fast response (∼5µs). The arrangement generating vortex beams switchable charges ±1 is also demonstrated, evidenced near- far-field interferograms. Our work expands scope exploiting dynamic phases arrangement, paving way multifunctional meta-optics.