Fractals are beautiful forms of geometric patterns, usually having high degrees of freedom of shape change. Recently, fractal and fractal‐like designs have aroused great interest in scientific research. Here, fractal‐like nano‐kirigami structures with rotational symmetries are proposed and demonstrated, in which topological morphologies can be transformed by growing fans and coiling units. Experimentally, the nano‐kirigami structures with different fractals are manipulated by using the capillary force‐induced 3D deformation process. Benefited from the fractal‐like designs, the structral deformations exhibit strong fractal dependence, with which the stress threshold and reflection spectrum can be tailored by changing the number of fans and coiling units. The modulation of fractal nano‐kirigami is further demonstrated by using the electrostatic forces when external voltage is applied. The fractal nano‐kirigami structures are also envisioned with capability of conveniently generating fractal‐dependent optical vortices. The special fractal design strategy in this work can bring new opportunities to functional 3D micro/nano structures with improved optical tunability and customization.

Dynamic color display can be realized by tunable optical metasurfaces based on the compositional or structural control. However, it is still a challenge to realize the efficient modulation by a single-field method. Here, we report a novel compositional and mechanical dual-altered rechargeable metasurface for reversible and broadband optical reconfiguration in both visible and near-infrared wavelength regions. By employing a simple fabrication and integration strategy, the continuous optical reconfiguration is manipulated through an electro-chemo-mechanical coupled process in a lithium ion battery, where lithiation and delithiation processes occur dynamically under a low electric voltage (≤1.5 V). By controlling the phase transformation from Si to LixSi, both structural morphology and optical scattering could be rapidly and dramatically tailored within 30 s, exhibiting high-contrast colorization and decolorization in a large-area nanofilm and showing long cyclic stability. Significant wide-angle reconfiguration of high-resolution structural colors in bowtie metasurfaces is demonstrated from anomalous reflection. The results provide a multifield mechanism for reconfigurable photonic devices, and the new platform can be introduced to the multidimensional information encryption and storage.

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