A Self-Adaptive Switchable Transparency/Invisibility Cloak Based on Programmable Metasurface

Abstract

Metamaterial-based invisibility cloaks have garnered significant attention in recent decades. However, due to the electromagnetic (EM) shielding provided by the cloak, the internal object can no longer communicate with the outside world in real-time in the invisibility frequency band, which significantly limits the practical application of the cloaks. In this paper, a self-adaptive switchable transparency/invisibility (SASTI) cloak is proposed and experimentally demonstrated using full-space (meaning transmission and reflection half-spaces) programmable metasurface. This cloak can be automatically switched between the invisibility and transparency modes based on real-time commands from a sensing antenna used to monitor external threat detection waves. In the transparency mode, the SASTI cloak is completely transparent to the EM waves and can be used as an information transmitter, enabling real-time communications between the internal cloaked object and the external cooperative equipment. In the invisibility mode, the SASTI cloak can achieve EM stealth and EM illusion against noncooperative detectors by changing its scattering characteristics. The proposed SASTI cloak is promising to be applied in future intelligent meta devices and information security systems.