Broadband achromatic metalens with wide field of view for linearly polarized light in the visible region

Abstract With flexibly manipulating wavefront in multiple dimensions at subwavelength scales, the metalens recently has caught growing attention. However, the presence of the chromatic aberration and monochromatic aberration hinder metalens, from wider applications. Here, we demonstrate a metalens based on the propagation phase, providing a diffraction-limited achromatic focusing with wide field of view (FOV) for linearly polarized light at visible region. In order to eliminate the aberrations, the aperture stop and the metasurface are separated in space and the particle swarm optimization algorithm is used to arrange the unit cells to achieve achromatic focusing. The simulation results show that the x -linearly polarized light of different wavelengths can be focused to the same plane within visible range from 0.473 to 0.6328 μm, featuring a wide field of view up to 80°. In addition, the architecture of the metalens is simplified to a single-layer metasurface by this method compared with the cascaded metalenses and conventional bulky optical systems, and we expect that our approach can underpin the development of integrated and visible imaging.