Kirigami Reconfigurable Gradient Metasurface

Abstract

Kirigami technique, a method to reconfigure structures via mechanical approaches, has received much attention in material science, due to its versatile and unconventional structural transformations. The counterparts in the electromagnetic metamaterial field has recently allowed for the tunable control of electromagnetic responses. However, they are limited to global tuning of absorption, chirality, etc., leaving much potential of controlling spatially varying distribution and therefore the optical wavefront unexploited. Here, the authors propose a class of kirigami‐based reconfigurable gradient metasurfaces through which the electromagnetic wavefront can be tuned over continuous‐state ranges by changing the meta‐structures from folded (compact) to unfolded (large surface) configurations. As the proof‐of‐concept, meta‐devices including switchable anomalous refractor and reconfigurable metalens are demonstrated both in simulations and experiments. Moreover, a new paradigm to mitigate chromatic dispersion is also realized by the kirigami‐based reconfigurable metalens, which is able to keep the focal length unchanged over a continuous frequency band by setting metalens with various folding states. Their approach provides a new alternative for designing reconfigurable gradient metasurface with additional mechanical properties and may have potential applications in advanced devices such as reconfigurable optical components and imaging system.

Recent Progress in Reconfigurable and Intelligent Metasurfaces: A Comprehensive Review of Tuning Mechanisms, Hardware Designs, and Applications

“…Summary of related works aimed to realize the tunable and reconfigurable metasurfaces by using different tuning mechanisms. Electrical Absorber [216] Phase Transition GST THz to Visible Electrical Modulator/wavefront engineering [199] Thermal Beam switching [245] VO 2 THz to Visible Electrical Beam manipulation [203] Optical Absorber [200] Thermal Absorber [202] Liquid Crystal GHz to Visible Electrical SAR imaging [212] Modulator [213] Beam steering [80] Mechanical MEMS GHz to Visible Electromechanical Modulator [238] Structural transformation GHz to Visible Mechanical Anomalous reflection/lens [246] Adaptive invisibility [247] Microfluids GHz to Visible Microfluids Polarization converter [241] Capacitance PIN diodes MHz to GHz Electrical Smart wireless power transfer [220] Sum and difference beams [221] Varactors MHz to GHz Electrical 3-Bit RIS [222]…”

“…The proposed design was applied to realize reconfigurable metalenses and tunable anomalous refractors. [246] Kirigami-inspired metamaterials have been proposed for adaptable invisibility management. [247] A reconfigurable origami metawall has been demonstrated for the tunable absorption and deflection of light, based on external mechanical stimuli (Figure 5f).…”

Active Ferromagnetic Metasurface with Topologically Protected Spin Texture for Spectral Filters

“…When microwaves are introduced into such magnetic systems, they couple to the spins and cause uniform and non-uniform spin precession, that is, ferromagnetic resonance at wavevector k = 0 and spin waves with k ≠ 0, respectively. For realizing the functionality of the microwave spectral filtering, different concepts could be applied such as microwave lumped elements, [13] mechanical engineering by the kirigami technique, [14] and metasurfaces composed of metallic and dielectric layers. [15] Ferromagnetic metasurfaces would be promising candidates for a new class of active (reconfigurable) metadevices [4,16,17] that manipulate reflected and transmitted microwave signals via spin waves and different magnetic states by modifying the external magnetic fields.…”

Mechatronic Reconfigurable Intelligent‐Surface‐Driven Indoor Fifth‐Generation Wireless Communication

“…Consequently, an electronically controlled RIS has problems such as high costs, high design complexity, difficult fabrication of the bias network, and continuous power consumption in the millimetre-wave region. [29][30][31] Recently, mechanically reconfigurable metasurfaces have been proposed to address these issues, [32][33][34][35] offering a new paradigm for the placement of electronic components within each unit cell.…”