Global Evolutionary Optimized Metasurface for Broad-angle Multisource Invisibility Cloaking

Abstract

Abstract As a new and advanced form of cloaking technology, metasurface cloaks have significant potential for widespread use in various fields owing to their excellent ultrathin and low-loss characteristics. Because of the principle of phase compensation based on incident direction, a metasurface cloak can operate only at a single specific angle (range). To be useful in real application scenarios, a cloak must be able to simultaneously handle multiple wide-angle detection waves. Various attempts have been made; however, currently, cloaks only work for a single detection source or are effective against incoming waves from a small incidence range. The design of a universal metasurface cloak that can flexibly respond to any number of sources at arbitrary incident angles remains a formidable challenge. Here, we present a global-evolution-optimization strategy for multisource and broad-angle meta-cloaks, which is based on a tunable metasurface to manipulate incoming waves at any angle over a wide range and is driven by an evolutionary game algorithm to satisfy the requirements for the cloaking of multiple simultaneous broad-angle incident sources. In experiments and simulations, the meta-cloak exhibited an impressive ability to render target objects invisible to both single and multiple incident waves at arbitrary angles, highly resembling background fields. This feasible cloaking strategy, which can be extended to any number of incident sources, provides an example of multisource wideband broad-angle scenario cloaking application.