Smart metasurface with self-adaptively reprogrammable functions

TLDR

Programmable metasurfaces can dynamically manipulate EM waves, yet they typically require manual control to switch functions. The authors propose a smart metasurface that self‑reprograms its functions autonomously. The metasurface incorporates sensors and an online feedback algorithm that senses the environment and autonomously adjusts its EM response, demonstrated with a gyroscope‑controlled beam‑steering device and extensible to other sensors. This approach enables unmanned devices that adapt their EM behavior to the surrounding environment.

Abstract

Intelligence at either the material or metamaterial level is a goal that researchers have been pursuing. From passive to active, metasurfaces have been developed to be programmable to dynamically and arbitrarily manipulate electromagnetic (EM) wavefields. However, the programmable metasurfaces require manual control to switch among different functionalities. Here, we put forth a smart metasurface that has self-adaptively reprogrammable functionalities without human participation. The smart metasurface is capable of sensing ambient environments by integrating an additional sensor(s) and can adaptively adjust its EM operational functionality through an unmanned sensing feedback system. As an illustrative example, we experimentally develop a motion-sensitive smart metasurface integrated with a three-axis gyroscope, which can adjust self-adaptively the EM radiation beams via different rotations of the metasurface. We develop an online feedback algorithm as the control software to make the smart metasurface achieve single-beam and multibeam steering and other dynamic reactions adaptively. The proposed metasurface is extendable to other physical sensors to detect the humidity, temperature, illuminating light, and so on. Our strategy will open up a new avenue for future unmanned devices that are consistent with the ambient environment.