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Stealth performance plays an increasingly important role in the evaluation of aircraft performance, while achieving excellent stealth performance in multiple frequency bands simultaneously remains a crucial challenge. Herein, a visible transparent wideband microwave absorber with infrared camouflage function is theoretically presented and experimentally demonstrated. The sample is composed of two radar absorption layers (RALs) and an infrared shielding layer (IRSL). In addition, the magnetic resonance model and the ohmic loss model are employed to strengthen the absorption of the designed RALs >90% in a broadband frequency range of 7–23 GHz with a relative bandwidth of 106.7%, and an average visible transmittance of ≈60%. Furthermore, IRSL is achieved by a designable digital frequency selective surface (FSS), which promotes a compatible design between infrared camouflaged emissivity and microwave absorption. These peculiar properties not only verify the feasibility of the proposed strategy for achieving suitable artificially designed IR digital camouflage patterns to meet various thermal camouflage environments, but also have promising application prospects in multispectral stealth. The additional visible light transparent feature makes it useful in compatible camouflage‐stealth facilities when requiring observing and operating in optical windows. [ABSTRACT FROM AUTHOR]

Metasurfaces composed of subwavelength structure arrays provide a diverse and powerful platform for generation of complicated electromagnetic (EM) fields and wavefronts manipulation and have triggered an unprecedented research upsurge in electromagnetism with the development of computer‐generated holography (CGH). Different from conventional scalar holograms only containing amplitude and phase properties, a vectorial hologram that benefits from the maneuverability of polarization of EM fields exhibits more immeasurable application potential and is simultaneously regarded as an urgent requirement. In this work, assisted by single completely spin‐decoupled meta‐particles, which perfectly combine the functions of simultaneous and independent amplitude and phase modulation of orthogonal polarization states containing left‐ and right‐handed circularly polarized (LCP&RCP) components, a vectorial hologram induced through eigenstates degeneracy with the ability of encoding arbitrary polarization is proposed in the microwave region. As the proof of concept, eight distinct holograms with specified polarizations and six‐channel polarization‐multiplexed hologram display are fabricated and characterized, further showcaing the versatility of the approach for the customization of arbitraty polarization and integration of reconstructed patterns. With the advantages of multi‐controllability and ultra‐compactness, the constructed monolayer completely spin‐decoupled paradigm for vectorial regulation may find prospective application aspects in spin detection, target perception, multi‐channel data encryption, and many other related fields. [ABSTRACT FROM AUTHOR]

Vortex beam carrying orbital angular momentum (OAM) has been experiencing a research upsurge attributed to its excellent communication capability, which also boosts the development of the OAM technology and promotes the application of the OAM generator. However, most of the existing designs of the OAM generators can only produce a small number of diverse OAM modes, and restrict the channel capacity of single OAM generator. Herein, an appealing strategy of six‐mode OAM generator based on helicity‐assisted full‐space metasurface is proposed to generate up to six diverse OAM modes by altering the polarization state, illumination region, and incidence direction of incident waves. Significantly, the designed OAM generator has high communication security because of its great information entropy, and the generated OAM modes possess the characteristics of high purity and low crosstalk which result from the orthogonal polarization states and unequal deflection angles of produced vortex beams. A proof‐of‐concept prototype is constructed to corroborate the validity of our methodology, and the results of simulations and experiments are in excellent agreement with theoretical predictions. This fire‐new OAM generator will possess a promising application prospect in communication systems, and may also provide an efficacious method to design multifunctional devices. [ABSTRACT FROM AUTHOR]

Surface plasmon polaritons (SPPs) have great applications in imaging, sensing, waveguide, and communication. Especially in the trending of electromagnetic (EM) metastructure field, researchers used the phase gradient design to achieve the efficient surface wave propagating performance ranging from GHz to THz. However, due to the intrinsic coupling interference from the current structure design, the phase and amplitude of different polarization are hard to freely manipulate simultaneously, making the design of multifunctional channels SPPs still a challenging project. Here, an anisotropic structure is proposed to realize independent control of both polarization and amplitude along different component of the wavefront. By analyzing the polarization dependent mechanism, the hexagon and half‐hexagon meta‐atom are introduced to the coupler structure to tailor the desired phase gradient along different directions under different polarized EM waves. Then the dispersion of coupler is further coupled with the propagating patch metasurface by optimization algorithm. As a result, the multifunctional SPP is achieved, and the multimode excitation can be generated under both linear and circular polarized incidence. Both simulation and experiment validate the effectiveness and wideband of spoof SPPs excitation performance, verifying that this method reduces the excitation condition of surface wave and improves the multiplexing effect of propagation channel. [ABSTRACT FROM AUTHOR]