Quasi-bound states in the continuum-based switchable light-field manipulator

Nonlocal metasurfaces, which support a collective mode, can be applied to manipulate the wavefront within the narrow band spectrum and do not operate other wavelengths. However, once fabricated, the tunability of those meta-devices is still a challenge. Here, we demonstrated a switchable all-dielectric nonlocal metasurface based on quasi-bound states in the continuum controlled by symmetry breaking. This device realizes the spatial light beam manipulation in the narrow band with switchable resonant wavelengths in different environment dielectric. We designed a nonlocal metasurface for beam focusing with a tunable wavelength in the communication band. We also designed a nonlocal metasurface for the generation of non diffraction Airy beams with tunable wavelength. These results will have potential applications in see-through display, large-capacity optical communications, nonlinear optics and imaging. (c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement