Mechanically reconfigurable metasurfaces: fabrications and applications

Optical metasurfaces that control the light wavefront play an important role in various applications, from imaging to spectroscopy. Over the past decade, metasurfaces-based dynamic optical manipulation has been broadly investigated on diverse reconfigurable mechanisms, providing a footing ground for light control in both spatial and temporal dimensions. Therein, mechanical reconfiguration, as one of the most direct methods, allows for the geometric alteration of constituent meta-atoms through external stimuli, thereby facilitating the evolution of metasurfaces from single function to multifunctional. This review focuses on introducing the primary mechanisms behind current mechanically reconfigurable metasurfaces, including mechanical, electrical, thermal, and optical modulations. Their emerging applications, such as dynamic focusing, image display, beam steering, polarization manipulator, thermal radiation, etc., are briefly highlighted. The main challenges and future development directions are also summarized within this dynamic and rapidly evolving research area, offering insights and future perspectives for advancements in the related fields.