Qinghua Liang

Nano‐kirigami method enables rich diversity of structural geometries that significantly broaden the functionalities of optical micro/nano‐devices. However, the methodologies of various nano‐kirigami are still limited and as a result, the chiral nano‐kirigami structure has yet been pushed to the limit for operation at visible wavelength region. Here, the merits of the various nano‐kirigami strategies are comprehensively explored and bio‐inspired nano‐cilia metasurface with enhanced circular dichroism at visible wavelengths is demonstrated. The stereo chiral nano‐cilia metasurface is designed with three‐fold rotational symmetry, which exhibits tuneable chiroptical responses when the nano‐cilia are deformed to form strong chiral light–matter interactions. By employing electron‐beam lithography (EBL) and focused ion beam (FIB) lithography, on‐chip nano‐cilia metasurfaces are experimentally realized in near‐infrared wavelengths region and at visible wavelengths, respectively, successfully validating the giant circular dichroism revealed in simulations. Our work is useful to broaden the existing platform of micro/nano‐scale manufacturing and could provide an effective method for the realization of versatile bioinspired nanostructures with profound chiroptical responses.